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Tony Beach

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A900 Update
« Reply #140 on: October 16, 2008, 02:49:12 am »

Quote from: ErikKaffehr
Which camera do you use?

I'm currently using the D300.
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Ray

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A900 Update
« Reply #141 on: October 16, 2008, 07:24:10 am »

Quote from: ErikKaffehr
Hi,

I can get tack sharp pictures hand held on all cameras with wide angles at around 1/10 or even 1/4 with AS..

Erik

I'm very impressed. Really tack sharp? Can you show us some 100% crops, comparing the same scene shot on a tripod with MLU enabled?

MLU shouldn't have much benefit at 1/10th or 1/4th, but just in case, have it enabled.

Several years ago when I bought my 5D and 24-105 zoom with an IS which it was claimed allowed up to 3 stops exposure advantage, the first shots I made were at 24mm and 1/6th and 1/13th sec, just to check how good that IS really was. I was a bit disappointed. I don't recall ever getting a truly sharp image at such slow shutter speeds. Probably good enough for 8x10" prints though.
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ErikKaffehr

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A900 Update
« Reply #142 on: October 16, 2008, 02:02:05 pm »

Hi Ray,

I probably shouldn't say "tack sharp" but reasonably sharp under the circumstances. I have not done any formal comparisons. I enclose a couple of 100% cropped pictures I shot on my summer holiday. They are taken with high ISO i a cathedral in Regensburg, Germany. Exposure is 60 mm at 1/4s and and 45mm 1/6s, both taken on Sony DSLR A700 with 1600 ISO and at full aperture. Lens is ZA 16-80/3.5-4.5.

Best regards
Erik

Quote from: Ray
I'm very impressed. Really tack sharp? Can you show us some 100% crops, comparing the same scene shot on a tripod with MLU enabled?

MLU shouldn't have much benefit at 1/10th or 1/4th, but just in case, have it enabled.

Several years ago when I bought my 5D and 24-105 zoom with an IS which it was claimed allowed up to 3 stops exposure advantage, the first shots I made were at 24mm and 1/6th and 1/13th sec, just to check how good that IS really was. I was a bit disappointed. I don't recall ever getting a truly sharp image at such slow shutter speeds. Probably good enough for 8x10" prints though.
« Last Edit: October 16, 2008, 02:06:43 pm by ErikKaffehr »
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ErikKaffehr

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A900 Update
« Reply #143 on: October 16, 2008, 02:16:26 pm »

Hi,

Thanks for info. I had Minoltas from SR-T 101, XM, XD7, Dynax 9Xi, KM 7D and Sonys DSLR A100 and DSLR A700. I also own a Pentax 67. In general I'm quite religious about mirror lockup, but I cannot say that I could ever confirm that it was benefitial. On the Sonys and the KM 7D it is available at the 2s self timer setting and that's something I generally use with the camera on tripod. On the Pentax I could see vibrations introduced by the focal plane shutter, I'm less certain I could see any effect of the MLU. On the early Minoltas I might have seen some minor vibrations  from the mirror when using a 500mm reflex lens.

My observations are from photography. I did not make any comparison with camera on tripod photographing USAF test targets or so.

Best regards
Erik

Quote from: Tony Beach
I'm currently using the D300.
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BernardLanguillier

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A900 Update
« Reply #144 on: October 16, 2008, 06:48:38 pm »

Quote from: ErikKaffehr
I probably shouldn't say "tack sharp" but reasonably sharp under the circumstances. I have not done any formal comparisons. I enclose a couple of 100% cropped pictures I shot on my summer holiday. They are taken with high ISO i a cathedral in Regensburg, Germany. Exposure is 60 mm at 1/4s and and 45mm 1/6s, both taken on Sony DSLR A700 with 1600 ISO and at full aperture. Lens is ZA 16-80/3.5-4.5.

That's maybe not 100% tack sharp, but that is for sure sharp enough and way sharper that would have been achieved without IS. Very impressive considering that you are shooting with the equivalent of a short tele on your APS sensor body.

Based on this, I would think that a wide lens openeds at 2.8 in your hands could deliver sharp results around 1/2 s in similar conditions. You could probably make do with 800ISO.

Cheers,
Bernard

Ray

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A900 Update
« Reply #145 on: October 16, 2008, 09:47:35 pm »

Quote from: ErikKaffehr
Hi Ray,

I probably shouldn't say "tack sharp" but reasonably sharp under the circumstances.

Erik,
That certainly is reasonably sharp under the circumstances. I wish I could have got such good results when I was in Italy a few years ago trying to comply with the usual no-flash rules that apply in most cathedrals. My camera was the 20D and my widest lens was the Sigma 15-30 (24-48 in 35mm terms) with no IS.

I really think it's time for an IS shoot-out between the A900 and the 1Ds3 (or the 5D2 if available).

If anyone is able or willing to do this, can I suggest the following procedure.

First take a series of shots with camera and selected lens on tripod, at various shutter speeds from 1/4 to 1/125th, with MLU enabled and MLU disabled. Use remote cord, switch off IS, and allow a couple of seconds after flipping the mirror to allow any vibrations to settle down before taking the shot.

Examine the results from both cameras in order to determine at what shutter speed the effects of mirror slap are greatest.

Then proceed to repeat all the shots at the same apertures, ISO settings and shutter speeds with cameras now off tripod, hand-held in the same position as they were when on tripod. Enable IS of course.

Ideally, it would also be useful if one could carry out such tests in a studio with variable lighting. One could then use the cameras at base ISO and the the lenses at their sharpest aperture for all shots. Without variable lighting, one will have to change aperture and/or ISO as one changes shutter speed, which will of course affect the quality of the shots to some degree. However, this should not invalidate the results as long as one compares same exposures (and same ISO and aperture) on and off the tripod.

The results of such an experiment should answer the following questions.

(1) At what shutter speed (or range of shutter speeds) is enabling MLU most beneficial for the camera and lens combination used?

(2) How much resolution is lost using IS with a hand-held shot as opposed to tripod without IS?

(3) To what extent, when the camera is hand-held, are the effects of mirror slap mitigated (if at all) at those critical shutter speeds when it's worst on the tripod?

Unfortunately, I'm unable to carry out such tests myself because I don't have an A900 (or any camera with an anti-shake sensor). Nor do I have a 1Ds2 or 5D2.
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ErikKaffehr

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A900 Update
« Reply #146 on: October 17, 2008, 12:31:14 am »

Hi Ray,

Just a comment on the lens. It's pretty nice in the center (the crops I uploaded were pretty central) at all apertures, but corners are bad if not stopped down, specially at 16 mm. I used to say that 16 mm was added with a wrench :-). But the lens is usable at all focal length at f/8. The stupid thing was that I had a 50/1.4 in my backpack but simply forgot about. I also took several exposures on each motive.

I may try your suggested test (on my A 700), but see a problem, if I use constant lighting I will probably get problems with different apertures.

By the way, the jury is still out on the A 900 at this place, as a former MF shooter I really appreciate sharpness. I made a couple of large prints at a pro lab using Durst Lambdas on 70x100 photographic paper and they really impress me. From the A700 I can make prints that I perceive as sharp in A2 (40x59 cm) on my Epson. I seldom make any larger enlargments. The extra pixels from the A 900 would certainly be welcome.

I see the A 900 as an investment with a couple of lenses. I can see that I have lateral CA on the 80-200/2.8 APO with the A 700 and I guess I would see more on full frame. My present thinking is that I would possibly buy a an A900 with a Sigma 12-24 (which is known to be surprisingly decent for the price), an Zeiss 24-70/2.8 and possibly 70-300G or 70-400G. I have not really impressed by the sample pictures I have seen from the 24-70/2.8 (on FF) , so I don't plan to buy until I have seen some MTF-tests. We have fortunately a monthly here in Sweden that makes MTF tests at the Hasselblad factory, they unfortunately only publish figures for MTF at 20 lines/mm although they get data for up to 60 lp/mm. I generally found "Foto" seems to have lens evaluations which are in agreement with my experience.

The 80-200/2.8 APO is still one of my best lenses in spite of the lateral color I can see, BTW, the major issue I have with it is the noisy autofocus. Lateral color is easily reduced in Lightroom, so I'm not so upset about it. I also have a Minolta 28-75/2.8 which is much better than the ZA 16-80, but the 16-80 is much more a practical lens and works really well at f/8 which is what I normally use. Convenience is a major factor.

I'm not really for fixed focals. I often find that I need variable focal length to be able to crop in the viewfinder and fitting vantage point to focal length is frequently not an option. This does not apply to telephoto, a telephoto lens that is to long I have not yet seen.

Best regards
Erik

Quote from: Ray
Erik,
That certainly is reasonably sharp under the circumstances. I wish I could have got such good results when I was in Italy a few years ago trying to comply with the usual no-flash rules that apply in most cathedrals. My camera was the 20D and my widest lens was the Sigma 15-30 (24-48 in 35mm terms) with no IS.

I really think it's time for an IS shoot-out between the A900 and the 1Ds3 (or the 5D2 if available).

If anyone is able or willing to do this, can I suggest the following procedure.

First take a series of shots with camera and selected lens on tripod, at various shutter speeds from 1/4 to 1/125th, with MLU enabled and MLU disabled. Use remote cord, switch off IS, and allow a couple of seconds after flipping the mirror to allow any vibrations to settle down before taking the shot.

Examine the results from both cameras in order to determine at what shutter speed the effects of mirror slap are greatest.

Then proceed to repeat all the shots at the same apertures, ISO settings and shutter speeds with cameras now off tripod, hand-held in the same position as they were when on tripod. Enable IS of course.

Ideally, it would also be useful if one could carry out such tests in a studio with variable lighting. One could then use the cameras at base ISO and the the lenses at their sharpest aperture for all shots. Without variable lighting, one will have to change aperture and/or ISO as one changes shutter speed, which will of course affect the quality of the shots to some degree. However, this should not invalidate the results as long as one compares same exposures (and same ISO and aperture) on and off the tripod.

The results of such an experiment should answer the following questions.

(1) At what shutter speed (or range of shutter speeds) is enabling MLU most beneficial for the camera and lens combination used?

(2) How much resolution is lost using IS with a hand-held shot as opposed to tripod without IS?

(3) To what extent, when the camera is hand-held, are the effects of mirror slap mitigated (if at all) at those critical shutter speeds when it's worst on the tripod?

Unfortunately, I'm unable to carry out such tests myself because I don't have an A900 (or any camera with an anti-shake sensor). Nor do I have a 1Ds2 or 5D2.
« Last Edit: October 17, 2008, 01:50:14 am by ErikKaffehr »
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Ray

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A900 Update
« Reply #147 on: October 17, 2008, 03:18:53 am »



Erik,
In my experience, Canon DSLRs produce very consistent sharpness from ISO 50 to ISO 400. There is probably a greater difference in DR than resolution, and changes in DR should have no bearing on the purpose of this test. If 1/4th sec to 1/125th is too great a range in relation to use of a sharp aperture, try 1/15th to 1/60th with just a 2 stop difference.

Quote
I see the A 900 as an investment with a couple of lenses. I can see that I have lateral CA on the 80-200/2.8 APO with the A 700 and I guess I would see more on full frame. My present thinking is that I would possibly buy a an A900 with a Sigma 12-24 (which is known to be surprisingly decent for the price), an Zeiss 24-70/2.8 and possibly 70-300G or 70-400G. I have not really impressed by the sample pictures I have seen from the 24-70/2.8 (on FF) , so I don't plan to buy until I have seen some MTF-tests. We have fortunately a monthly here in Sweden that makes MTF tests at the Hasselblad factory, they unfortunately only publish figures for MTF at 20 lines/mm although they get data for up to 60 lp/mm. I generally found "Foto" seems to have lens evaluations which are in agreement with my experience.

I'll be very interested to see test reports on that 70-400G, as well as the Sony 16-35. I could get by with just those two lenses plus what I already have, which includes the Minolta 35-105 and a few primes.
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ErikKaffehr

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A900 Update
« Reply #148 on: October 17, 2008, 08:50:18 am »

Hi Ray,

German biweekly C't (like Computer Technology) had a shootout between different systems. Including Canon 24-105 IS and Sony Alpha 700 with Minolta 24-105. They used a test rig oscillating with different frequencies. In their test both of the above were among the best systems tested, with the Sony Alpha having the edge, as far as I can recall. I'll be nasty enough to post the results in the week end.

Erik


Quote from: Ray
Erik,
In my experience, Canon DSLRs produce very consistent sharpness from ISO 50 to ISO 400. There is probably a greater difference in DR than resolution, and changes in DR should have no bearing on the purpose of this test. If 1/4th sec to 1/125th is too great a range in relation to use of a sharp aperture, try 1/15th to 1/60th with just a 2 stop difference.



I'll be very interested to see test reports on that 70-400G, as well as the Sony 16-35. I could get by with just those two lenses plus what I already have, which includes the Minolta 35-105 and a few primes.
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BernardLanguillier

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A900 Update
« Reply #149 on: October 22, 2008, 04:57:33 pm »

DPreview A900 test is out.

Low ISO image quality appears to be very much MFDB class with a DR of 12.6 stops, better than most current 22MP offerings from Phase and Leaf.

Cheers,
Bernard

Ray

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A900 Update
« Reply #150 on: October 22, 2008, 08:46:16 pm »

Quote from: BernardLanguillier
DPreview A900 test is out.

Low ISO image quality appears to be very much MFDB class with a DR of 12.6 stops, better than most current 22MP offerings from Phase and Leaf.

Cheers,
Bernard

I guess there has to be a trade-off somewhere. One can't have it all, in one camera...yet. It looks as though the A900 is a camera that will appeal more to MFDB users who want an inexpensive system for studio work, rather than travellers who want a versatile system for all occasions, including specifically, low light shooting without flash and wildlife shooting with telephoto lens in less than ideal lighting.

I might have to give this camera a miss, with some regret because, as I've already mentioned, I have a few Minolta lenses which I never bothered selling when I switched to Canon several years ago.
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douglasf13

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A900 Update
« Reply #151 on: October 22, 2008, 08:52:40 pm »

Quote from: Ray
I guess there has to be a trade-off somewhere. One can't have it all, in one camera...yet. It looks as though the A900 is a camera that will appeal more to MFDB users who want an inexpensive system for studio work, rather than travellers who want a versatile system for all occasions, including specifically, low light shooting without flash and wildlife shooting with telephoto lens in less than ideal lighting.

I might have to give this camera a miss, with some regret because, as I've already mentioned, I have a few Minolta lenses which I never bothered selling when I switched to Canon several years ago.


  While there is always going to be tradeoffs with cameras, the A900's higher ISO's are still very usable when compared to the D700 or 1dsiii at the same size print.  It may not be quite as good, but I don't believe it's a deal breaker for the kind of shooting you describe.  Either way, if high ISO is more important to you than resolution and dynamic range, the D700 is a no brainer.
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Ray

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A900 Update
« Reply #152 on: October 22, 2008, 10:28:45 pm »

Quote from: douglasf13
While there is always going to be tradeoffs with cameras, the A900's higher ISO's are still very usable when compared to the D700 or 1dsiii at the same size print.  It may not be quite as good, but I don't believe it's a deal breaker for the kind of shooting you describe.  Either way, if high ISO is more important to you than resolution and dynamic range, the D700 is a no brainer.

High ISO is never more important than resolution. The height of the A900 ISO settings is just fine. It's the resolution at those high ISO settings that is disappointing.

In most reviews, there's an emphasis on jpeg quality and strict adherence to camera settings such that, if one camera doesn't have an ISO 6400 setting, it will not be compared with another camera that does have an ISO 6400 setting. The fact that ISO 6400, for all practical purposes, is ISO 3200 underexposed one stop appears to be of no interest to reviewers.

However, from my perspective I don't really care what the ISO setting is called. I simply want the best quality image I can get under the lighting conditions. If the shot requires, for an appropriate shutter speed at the maximum aperture, an underexposure of one stop at ISO 3200, then so be it. It would be absurd to think, "Oops! I can't take this shot. My camera doesn't have an ISO 6400 setting."

When one disregards the labelling of the ISO settings and one just compares images taken at the same aperture and shutter speed, the D3 has at best only a 1/2 stop noise/DR advantage over the 5D, according to my own tests, shooting RAW. There seems to be a suggestion in the dpreview review of the A900 that the D700 has a lower DR than the D3 comparing jpeg output. I can find no RAW image DR comparisons between the D700 and D3.

The bottom line for me is, I cannot justify switching systems for the sake of a 1/2 stop high-ISO noise improvement and no increase in pixel count, so the D700 is not an option for me, after due consideration. Maybe the D700 successor will be.
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BernardLanguillier

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A900 Update
« Reply #153 on: October 22, 2008, 11:37:14 pm »

Quote from: Ray
The bottom line for me is, I cannot justify switching systems for the sake of a 1/2 stop high-ISO noise improvement and no increase in pixel count, so the D700 is not an option for me, after due consideration. Maybe the D700 successor will be.

So your conclusion is... the crowd can't hold its breath... a contest has never been that close before... the tension is unbearable... you will get a 5DII when it becomes available?

Cheers,
Bernard

Ray

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A900 Update
« Reply #154 on: October 23, 2008, 02:05:30 am »

Quote from: BernardLanguillier
So your conclusion is... the crowd can't hold its breath... a contest has never been that close before... the tension is unbearable... you will get a 5DII when it becomes available?

Cheers,
Bernard

Not necessarily, Bernard. I'm in no hurry   . Got plenty of cameras to play with. It'll probably be a while before the 5D2 becomes readily available. In the meantime, perhaps Nikon will announce an irresistable successor to the D700.

I picked up a copy of the Nikkor 14-24/2.8 yesterday. Managed to fit it to my 5D body without too much hassle, using the Mark Welsh adapter which I ordered about 8 months ago but received just a couple of weeks ago.

One thing I've learned about this costly DSLR upgrade process is not to rush into purchases. There's often something better around the corner.
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aaykay

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A900 Update
« Reply #155 on: October 23, 2008, 07:40:47 pm »

Quote from: BernardLanguillier
So your conclusion is... the crowd can't hold its breath... a contest has never been that close before... the tension is unbearable... you will get a 5DII when it becomes available?

Cheers,
Bernard

I would have predicted this several posts back, except for the fact that he kept on circling around with the same theme for a while, to finally go back to what makes the best sense for him - pick up a Canon body !  
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Ray

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A900 Update
« Reply #156 on: October 23, 2008, 08:53:56 pm »

Quote from: aaykay
I would have predicted this several posts back, except for the fact that he kept on circling around with the same theme for a while, to finally go back to what makes the best sense for him - pick up a Canon body !  

What theme would you like me to circle around with? Unlike Michael, I can't afford to buy any equipment that takes my fancy merely because it might have one or two small features that my current equipment lacks.

So far, I haven't seen any direct and meaningful comparisons between the A900 and 5D2 or between the best lenses for the A900 and the equivalent best lenses available with Canon mount. The image comparisons with the 1Ds3 I've seen so far seem to indicate that any advantage in respect of resolution and DR at base ISO, that the A900 appears to have, is quite small and clearly not as great as the advantage that the 1Ds3 has at high ISO.

If there is any reason for a photographer to switch from a Canon system to a Sony system, I haven't seen it yet, in this thread or at Dpreview and Imaging Resource, but I've been looking hard.
 
I'm sorry that you seem to take this so personally. You can criticise Canon equipment as much as you like. You won't hurt me as long as you stick to the facts.  
« Last Edit: October 23, 2008, 08:57:47 pm by Ray »
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ErikKaffehr

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A900 Update
« Reply #157 on: October 24, 2008, 01:22:35 am »

Hi,

I guess that the Sony A900 is good enough so Sony/Minolta owners don't need to jump wagons to Canon or Nikon. I think that lenses may matter, but I have not seen any evidence yet that Sony lenses perform better than the Canon lens line. The only advantage the Sony has over the competition in picture taking capability is the in body image stabilization which works with all lenses.

There may be other aspects:
- Speed and exactness of autofocus
- Frame rate
- Weight of body
- Vibrations, dampening sound level
- User interface

I'm quite skeptical about reviews as I never use JPEG and most comparisons test JPEG processing.

Best regards
Erik

Quote from: Ray
What theme would you like me to circle around with? Unlike Michael, I can't afford to buy any equipment that takes my fancy merely because it might have one or two small features that my current equipment lacks.

So far, I haven't seen any direct and meaningful comparisons between the A900 and 5D2 or between the best lenses for the A900 and the equivalent best lenses available with Canon mount. The image comparisons with the 1Ds3 I've seen so far seem to indicate that any advantage in respect of resolution and DR at base ISO, that the A900 appears to have, is quite small and clearly not as great as the advantage that the 1Ds3 has at high ISO.

If there is any reason for a photographer to switch from a Canon system to a Sony system, I haven't seen it yet, in this thread or at Dpreview and Imaging Resource, but I've been looking hard.
 
I'm sorry that you seem to take this so personally. You can criticise Canon equipment as much as you like. You won't hurt me as long as you stick to the facts.  
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Fine_Art

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A900 Update
« Reply #158 on: November 02, 2008, 02:08:14 am »

Those of you that were wondering how the A900 works with Sony lenses in the corners should look at these.
This is with the Zeiss 135 AF wide open at 1.8.
http://www.dyxum.com/dforum/forum_posts.as...=37672&PN=1
This guy does great work. He's linked full size shots as well.
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ErikKaffehr

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A900 Update
« Reply #159 on: November 10, 2008, 03:41:29 pm »

Hi,

I have done some testing on my Alpha 700 according to Ray's suggestions. The results were not really what I expected. I did not have the time to make a good summary. Here is what I have done:

A series of tests from 1/8s to 1/125s with a 80-200/2.8 using a Velbon Sherpa 630 CF tripod and a RRS BH40 head, all tripod based exposures with cable release

A) Tripod, mirror lock up, no AntiShake
 Tripod, no mirror lock up, no AntiShake
C) Tripod, no mirror lock up, AntiShake
D) Free hand, AntiShake

- The A-series was clearly much better than the rest
- Antishake did't really help on tripod
- The freehand with AntiShake were reasonably good

Best regards
Erik


Quote from: Ray
Erik,
That certainly is reasonably sharp under the circumstances. I wish I could have got such good results when I was in Italy a few years ago trying to comply with the usual no-flash rules that apply in most cathedrals. My camera was the 20D and my widest lens was the Sigma 15-30 (24-48 in 35mm terms) with no IS.

I really think it's time for an IS shoot-out between the A900 and the 1Ds3 (or the 5D2 if available).

If anyone is able or willing to do this, can I suggest the following procedure.

First take a series of shots with camera and selected lens on tripod, at various shutter speeds from 1/4 to 1/125th, with MLU enabled and MLU disabled. Use remote cord, switch off IS, and allow a couple of seconds after flipping the mirror to allow any vibrations to settle down before taking the shot.

Examine the results from both cameras in order to determine at what shutter speed the effects of mirror slap are greatest.

Then proceed to repeat all the shots at the same apertures, ISO settings and shutter speeds with cameras now off tripod, hand-held in the same position as they were when on tripod. Enable IS of course.

Ideally, it would also be useful if one could carry out such tests in a studio with variable lighting. One could then use the cameras at base ISO and the the lenses at their sharpest aperture for all shots. Without variable lighting, one will have to change aperture and/or ISO as one changes shutter speed, which will of course affect the quality of the shots to some degree. However, this should not invalidate the results as long as one compares same exposures (and same ISO and aperture) on and off the tripod.

The results of such an experiment should answer the following questions.

(1) At what shutter speed (or range of shutter speeds) is enabling MLU most beneficial for the camera and lens combination used?

(2) How much resolution is lost using IS with a hand-held shot as opposed to tripod without IS?

(3) To what extent, when the camera is hand-held, are the effects of mirror slap mitigated (if at all) at those critical shutter speeds when it's worst on the tripod?

Unfortunately, I'm unable to carry out such tests myself because I don't have an A900 (or any camera with an anti-shake sensor). Nor do I have a 1Ds2 or 5D2.
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