Luminous Landscape Forum
Equipment & Techniques => Medium Format / Film / Digital Backs – and Large Sensor Photography => Topic started by: Jozef Zajaz on October 30, 2011, 08:20:20 pm
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Hi!
I'm going over todays test shoot. Was testing the iq 180 in studio today. Pretty heavy, snapping alot of pictures. Not sure if its just me but i think i can see some noise at iso 100 on the pics in the end of the shoot. The back fellt awfully warm compared to my p30+.
Anyone else experienced this?
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I'm going over todays test shoot. Was testing the iq 180 in studio today. Pretty heavy, snapping alot of pictures. Not sure if its just me but i think i can see some noise at iso 100 on the pics in the end of the shoot. The back fellt awfully warm compared to my p30+.
Hi Jozef,
Hard to comment without some visual feedback about what you call 'some noise'. How was the exposure in the sense of an ETTR exposure? From the DxOMark website it seems that there is an almost 2-stop overexposure latitude in the IQ180 ISO rating.
Cheers,
Bart
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Hi Jozef,
Hard to comment without some visual feedback about what you call 'some noise'. How was the exposure in the sense of an ETTR exposure? From the DxOMark website it seems that there is an almost 2-stop overexposure latitude in the IQ180 ISO rating.
Cheers,
Bart
"How was the exposure in the sense of an ETTR exposure? From the DxOMark website it seems that there is an almost 2-stop overexposure latitude in the IQ180 ISO rating.
"
Makes no sense at all to me. Please explain :)
Will post pics when i can.
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I don't have an IQ180, rather a Aptus 12 so just the base sensor similarities shared, but there is always noise in every ISO 100 shot. I haven't figured out the rubric so far, but some shots have more noise than others - maybe heat, but there's the fan running all the time. Why not shoot at ISO 50? Or even the ISO 30 on the IQ180?
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Hi,
ISO rating on the back is far to high, probably in order to protect highlights. At least according to measurements by DxO.
So it may be possible to increase exposure significantly without clipping highlights.
Which raw developer do you use?
Best regards
Erik
"How was the exposure in the sense of an ETTR exposure? From the DxOMark website it seems that there is an almost 2-stop overexposure latitude in the IQ180 ISO rating.
"
Makes no sense at all to me. Please explain :)
Will post pics when i can.
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Ah I C
Capture one 6.3 of course.
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Hi!
I'm going over todays test shoot. Was testing the iq 180 in studio today. Pretty heavy, snapping alot of pictures. Not sure if its just me but i think i can see some noise at iso 100 on the pics in the end of the shoot. The back fellt awfully warm compared to my p30+.
Anyone else experienced this?
The OP's point is that there was an unacceptable degree of thermal dark noise kicking in as the shooting session went on. This stuff about ISO settings and ETTR is a red herring in this context - that would be a problem of readout and poisson noise; which may indeed be a sideline issue, but it is not one which varies with the "heaviness" of the camera usage.
So the real question is - since "The back fellt awfully warm compared to my p30+", have PhaseOne sacrificed some of their famous thermal management on moving from the P+ series to the IQ series?
You could get away with poorer thermal management with Kodak CCDs, since as CCDs go, they have rather low dark noise at a given temperature. But the IQ backs only use Dalsa CCDs, which are much higher in dark noise than the equivalent-generation Kodaks. If a manufacturer lets a Dalsa sensor get warm - image quality will suffer.
Is it possible to get a sensor temperature readout from any of the PhaseOne backs? My old Kodak Proback 645M displays the sensor temperature in real-time when tethered, and I know the Pentax 645D writes the temperature to its EXIF headers. Any other backs do one of these things?
Ray
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I know the Pentax 645D writes the temperature to its EXIF headers. Any other backs do one of these things?
Ray
It does? How do I find that? It certainly is not in the metadata in Bridge. Not that I can see, anyway. I didn't even know the camera had a thermometer.
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Hard to comment without some visual feedback about what you call 'some noise'.
+1. We need a visual example to understand what you mean by "some noise".
Also would be good to know:
- which firmware version you are running
- whether you were using it on zero latency or standard latency
Generally speaking it will be faster for you if you start such questions with your dealer (assuming you have a dealer that you have a good relationship with) as it will eliminate the back and forth on such basic questions and eliminate potential red-herrings; the forum is really useful as a resource, but more useful if you've already done some basic questions with your dealer (or if you want other's opinions on what the dealer is telling you) and you're asking the forum for verification/further-opinions.
Doug Peterson (e-mail Me) (doug@captureintegration.com)
__________________
Head of Technical Services, Capture Integration
Phase One Partner of the Year
Leaf, Leica, Cambo, Arca Swiss, Canon, Apple, Profoto, Broncolor, Eizo & More
National: 877.217.9870 | Cell: 740.707.2183
Newsletter (http://"http://www.captureintegration.com/our-company/newsletters/") | RSS Feed (http://"http://www.captureintegration.com/2008/08/11/rss-feeds/")
Buy Capture One 6 at 10% off (http://"http://www.captureintegration.com/phase-one/buy-capture-one/")
Masters Series Workshop:
New England Landscape - Fall Color (Oct 5-8) (http://"http://www.captureintegration.com/2011/06/30/nelandscape/")
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It does? How do I find that? It certainly is not in the metadata in Bridge. Not that I can see, anyway. I didn't even know the camera had a thermometer.
Well, someone posted a link to a large set of indoor 645D test images in the past year or so, and when I examined the metadata (of which there was tonnes), the temperature was given in each one. I was impressed to find that it hardly changed at all in the course of a sequence of multi-second exposures. I haven't handled a 645D, so I've no idea whether this is written by default or how to activate it if it's not. Worth digging into the small print in the user manual perhaps? Or try running Exiftool on one of your files.
Ray
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+1. We need a visual example to understand what you mean by "some noise".
Also would be good to know:
- which firmware version you are running
- whether you were using it on zero latency or standard latency
Generally speaking it will be faster for you if you start such questions with your dealer (assuming you have a dealer that you have a good relationship with) as it will eliminate the back and forth on such basic questions and eliminate potential red-herrings; the forum is really useful as a resource, but more useful if you've already done some basic questions with your dealer (or if you want other's opinions on what the dealer is telling you) and you're asking the forum for verification/further-opinions.
Doug Peterson (e-mail Me) (doug@captureintegration.com)
__________________
Head of Technical Services, Capture Integration
Phase One Partner of the Year
Leaf, Leica, Cambo, Arca Swiss, Canon, Apple, Profoto, Broncolor, Eizo & More
National: 877.217.9870 | Cell: 740.707.2183
Newsletter (http://"http://www.captureintegration.com/our-company/newsletters/") | RSS Feed (http://"http://www.captureintegration.com/2008/08/11/rss-feeds/")
Buy Capture One 6 at 10% off (http://"http://www.captureintegration.com/phase-one/buy-capture-one/")
Masters Series Workshop:
New England Landscape - Fall Color (Oct 5-8) (http://"http://www.captureintegration.com/2011/06/30/nelandscape/")
My dealer is visiting me on thursday. Will take it up with him then :)
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Ray,
Yes, the Sinarbacks do indicate the sensor's temperature as well.
Thierry
Is it possible to get a sensor temperature readout from any of the PhaseOne backs? My old Kodak Proback 645M displays the sensor temperature in real-time when tethered, and I know the Pentax 645D writes the temperature to its EXIF headers. Any other backs do one of these things?
Ray
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Generally speaking it will be faster for you if you start such questions with your dealer (assuming you have a dealer that you have a good relationship with) as it will eliminate the back and forth on such basic questions and eliminate potential red-herrings; the forum is really useful as a resource, but more useful if you've already done some basic questions with your dealer (or if you want other's opinions on what the dealer is telling you) and you're asking the forum for verification/further-opinions.
Doug,
It would be a beautiful world if that were really true. Typically I get more and better information through the forums on practical working questions about the gear or how to best use it. Dealers can usually answer policy and pricing questions and sometimes stuff about software/firmware too. In general dealers a loathe to directly answer questions that expose the pink underbelly of the beast, but users are more than happy too.
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Doug,
It would be a beautiful world if that were really true. Typically I get more and better information through the forums on practical working questions about the gear or how to best use it. Dealers can usually answer policy and pricing questions and sometimes stuff about software/firmware too. In general dealers a loathe to directly answer questions that expose the pink underbelly of the beast, but users are more than happy too.
It's unfortunate that the majority of dealers fall into this category. That said, there are dealers out there who are truly responsive, who actually encourage the sticky issues - so that they learn - and have the benefit of an extremely large sample size (hundreds if not thousands of user experiences) to draw from compared to a public forum with a smaller select number of user experiences with which to troubleshoot any issues one would have. Those same dealers also can have very deep access and input into a given manufacturer's development and engineering team, can ascertain difficult to obtain information, and even effect change rapidly with that direct interaction for a client.
However, I also find the forum to be valuable, because while the sample size of users is relatively small compared to the overall installed base of the product, the users who are present are often very forthcoming in their desire to be of help. You just have to be aware the information isn't always accurate nor reflective of what is typical of the product's performance. But on the whole, I think good, specialized dealers (who are, by the way, available to just about anyone who chooses to do business with them, as opposed to poor, unresponsive, unknowledgeable dealers) and savvy forum contributors make a good 1-2 punch, as Jozef is finding out.
Steve Hendrix
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Steve,
Maybe, but still I prefer to hear from users who shoot the cameras hard and try different things to get jobs done, because they'll encounter the problems and issues like the OP's question more often. That's why this forum here at LuLa is great - you get both the users and the dealers at the same time.
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Steve,
Maybe, but still I prefer to hear from users who shoot the cameras hard and try different things to get jobs done, because they'll encounter the problems and issues like the OP's question more often. That's why this forum here at LuLa is great - you get both the users and the dealers at the same time.
Ummm...well I think that is what I just said if you'll go back and read my post. ::)
That said, working with a specialized dealer does not exclude you from end user experiences, in fact, it expands upon that because the users who work the camera hard are the ones we hear from the most, and our sample rate - again - is hundreds, thousands of user experiences.
Both sources are valuable (like I said). :)
Steve Hendrix
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What I am wondering is why all that technical advices in Phase One product questions in LuLu and GetDpi come from Capture Integration guys but not from Phase One people.
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Steve, who would you contact if you needed info on the AFi or any Rollei stuff? ;)
Unfortunately, mostly I give information to the dealers on the equipment I use, and they are often surprised at all the things it can do. I've only gotten information on the capture one software from dealers. Hasselblad tech guys know a bit about Rollei, and Yair knows a fair bit about it but these aren't dealers. I've gotten almost everything I know about the rollei 6008AF, Hy6/AFi and X-Act2 from other users, most from this forum, and I'm thankful for it.
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This gets away from the OP, I have always found Phase One's setup a bit odd. No phone support, yes you enter a tech support issue and get a case number but still I have always liked to have to option to speak to someone. And most times they are responsive, being in Denmark and many time zones away.
The dealers I have used in the past Capture Integration and Digital Transitions have been very helpful but as a rule most companies stillhave a tech support line, and dealer support structure. I have no experience with Sinar/Lear/Hassiblad, just Phase One for medium format so I don't know if they offer a person at the other end.
Eric's point is well taken, as many times in the past I tended to lead by forum then go to dealer, however recently I have reversed this path. I also feel location is very key to this issue. With Canon or Nikon or any other 35mm most any city in the US will have a local knowledge base, however with Phase One, you are very limited to hands on learning, hardware or software unless you live near or in the Major US cities. This
more than anything else is what caused me to be forum first dealer second.
Actually the dealer presence on this forum has grown and that is a positive to me.
Paul Caldwell
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I'm in Phoenix not a dealer near me for hundreds of miles but my phone works great and get great support from them. Okay I own a forum and it is very useful no question but sometimes a dealer truly has the correct solution for you and I would not buy any of this gear without a dealer backing me especially with a back i bought.
But that is not why I posted today. The reality is going back to the Op's question is any CCD sensor will create noise when it gets hot or very warm. The question is when does that happen. Without knowing how warm your back got its hard for us to say but the reality is sure it will happen at some temperature point. I shoot my Tech cam at zero latency and if i keep it on all the time it will get very warm and it will most likely create noise if i let it get to a certain point. I just don't know exactly when that is. So after heavy use sure it is certainly possible for any of the backs be it Hassy, Phase, Leaf or Sinar that a back can get hot enough to do it. The question is when does it occur. Each system has cooling systems built in be it passive or fans but I'm not sure which one one could say better handles it or not and don't really care what each one would claim either. I live in the desert it gets hotter than blazing hell here and i do take some precautions working in the heat just like I would with myself at 120 degrees bearing down on me. Its a sensor that electricity running through it and given the ambient temperture here it only makes sense it will get hot. So really after heavy use i would not be surprised if noise did enter into the fold. The real question is when does tat occur. Not sure anyone truly has a answer for that.
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The reality is going back to the Op's question is any CCD sensor will create noise when it gets hot or very warm. The question is when does that happen.
Hi Guy,
It's not really a "when" does it happen question. CCD sensors typically double their so-called dark count (http://www.ccd.com/ccd109.html) for each six degrees Celsius (or Kelvin) increase in temperature. So there will be noise, especially with increased temperature.
Whether it will be noticeable depends on how much noise there is (which varies between sensor designs), but also in relation to the actual signal (the exposure) level (hence my earlier remark about the almost 2 stops 'underexposure' for the ISO value). As the above link says, "Having lower dark count is always desirable, but there comes a point when other factors such as shot noise or S/N supercede dark count considerations".
So there are 2 factors that matter, CCD sensor temperature controlled by cooling, and the absolute amount of dark count during the 'exposure' time versus the actual exposure level.
Cheers,
Bart
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Bart,
Thanks for the info. Is that true for both Dalsa and Kodak sensors? I'm not remembering any grain in the kodak sensor based backs that I've shot with (at base ISO), and only now notice it with the Aptus 12.
And regarding dealers - I had a prob with my Aptus back and my dealer went to bat for me on getting it sent in for service, but I ended up with the e-mail and phone numbers of nearly everyone at Leaf and a few guys in the tech dept at Phase too. They will talk to you on the phone if you can get to them. That was helpful I guess. Good dealers usually have tech guys, but these guys spend their time getting to know the software mostly. But having written the above - anyone notice the Hasselblad web store? I ended up buying my CF-ii-39MS direct from Hasselblad and did so for much less than the dealers I spoke to could offer. The opportunity to eliminate the dealers is out there to be seen - I mean HB already provides tech support and service directly, and phone sales as well as web sales.
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Is that true for both Dalsa and Kodak sensors? I'm not remembering any grain in the kodak sensor based backs that I've shot with (at base ISO), and only now notice it with the Aptus 12.
Hi Eric,
AFAIK it's a property of silicon based image sensors. Do note that we're not talking about total noise, but only the "dark count" component of noise. In addition we'll have read noise and then photon shot noise. As always, when the signal to noise ratio is high enough we won't notice the noise floor because the absolute amount of shot noise becomes significantly higher than the floor.
When I look at the Maker notes in my camera's EXIF data with Phil Harvey's EXIFtool, there is a field that holds the camera temperature. I don't know where inside the camera it's recorded, and maybe not all manufacturers record it.
Cheers,
Bart
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Why not post 2 samples (crops) 1 of the first few images and 1 of the last few images of the series you were shooting so we may get an idea of what you see.
What exposure time were you using or were you shooting a fashion setup that required rapid shooting?