Dslr landscape technique (stitching related)

[MarkL]

I’m very new to digital so I’m interested in hearing other peoples’ methods. I have recently tried using my D700 for shooting landscapes rather than my usual Ebony with 6x7 back and have using a totally different approach centred around being able to shoot quickly in the field when the light is changing fast but still getting good quality by stitching.

Shooting

1.   I set the camera to lowest iso (200), matrix metering, auto white balance and aperture priority. Seriously bear with me on this!

2.   Level tripod base and select lens

3.   Shoot the frames refocusing on each horizontal pass to get the best focus for the frame. Sometimes you might need to shoot a frame multiple times with different focus points if it is required (not too often).

Post

1.   Adjust and process each raw individually but setting the most appropriate white balance to be the same across the frames. Export as tiffs.

2.   Focus blend any focus bracketed frames in helicon focus (if there are any) and save output files as tiff

3.   Photomerge in photoshop (seems to consistently produce the best results)

Amazingly what could be considered to be a very ‘slap dash’ approach, breaking many of the rules for stitching (variable exposure etc), works extremely well. I have had panos where some frames were originally exposed 4 stops differently and still had no problems. The good meter on the D700 and ability to expose each frame differently removes the need for multiple passes for HDR or other blending. No metering or consideration of exposure needs to be done and any dof issues are alleviated by focusing for each frame. The final stitched file requires minimal work.

It sounds mad but it works very well for me. I’m interested in any feedback.

[button]

I really like to use a zoom lens for stitches.  I'll move around with the camera and find the best composition.  I then mount the camera on the tripod at that spot- this lets me check my composition before the stitch.  Then, I zoom in, take the number of shots (frames) that I need, and move on.  I've been experimenting with T/S lenses, but I find optimizing the tilt and focus difficult to do quickly.  One question I have for you, Mark:  how do you deal with homogeneous blue sky at different exposures?  Sky blending is pretty tough as is!

John

[OldRoy]

... how do you deal with homogeneous blue sky at different exposures?  Sky blending is pretty tough as is!

John

Hi
I do a few spherical panoramas, mostly interiors, but also quite a few single row exterior landscapes. I don't claim to be any great expert however. I have been using PTGui for about a year for stitching. It contains its own blending code and works extremely well in all respects. It also does HDR blending, however I can't get on with this and pre-blend using Enfuse. The alternatives for blending, which can be selected within PTGui, are Enblend and Smartblend, which also work well (free/shareware). Sometimes one application might give a better result than another, however I've not analysed the parameters involved at all. In all three cases the blending on skies looks pretty good to me. When I first started doing this - using CS2 - it defeated me completely, particularly where blue skies were concerned. The above solutions work satisfactorily for my humble requirements and are well worth trying I think.

PTGui is not a particularly easy program to use, however the panoguide.com forum is extremely informative. I have also tried PTAssembler which is similar, inexpensive, and suitable for non-spherical single and multi-row panoramas. It utilises the same blending applications (as far as I recall) but I didn't like the UI so much; however it may have been improved since I last used it.

I hope these suggestions may be useful. If I can assist further please ask.

Roy

[button]

Hi
I do a few spherical panoramas, mostly interiors, but also quite a few single row exterior landscapes. I don't claim to be any great expert however. I have been using PTGui for about a year for stitching. It contains its own blending code and works extremely well in all respects. It also does HDR blending, however I can't get on with this and pre-blend using Enfuse. The alternatives for blending, which can be selected within PTGui, are Enblend and Smartblend, which also work well (free/shareware). Sometimes one application might give a better result than another, however I've not analysed the parameters involved at all. In all three cases the blending on skies looks pretty good to me. When I first started doing this - using CS2 - it defeated me completely, particularly where blue skies were concerned. The above solutions work satisfactorily for my humble requirements and are well worth trying I think.

PTGui is not a particularly easy program to use, however the panoguide.com forum is extremely informative. I have also tried PTAssembler which is similar, inexpensive, and suitable for non-spherical single and multi-row panoramas. It utilises the same blending applications (as far as I recall) but I didn't like the UI so much; however it may have been improved since I last used it.

I hope these suggestions may be useful. If I can assist further please ask.

Roy

Thanks, Roy, for your helpful response.  I have used PTGui for about a year now and really like the program- especially the "control point" editor.  One thing that I haven't been able to do yet is get the "straighten panorama" feature to work (I get some kind of error).  Have you had this problem?  Mark, I don't mean to hijack your thread- maybe something will come out of this that will help us both.

John

[Ben Rubinstein]

That you can leave the software to equalise any exposure differences doesn't avoid the fact that you are not optimising the exposure, if it has to pull shadows then you are getting less detail and more noise. I usually stitch at iso 400 to freeze leaf movement with a polariser, ETTR is pretty essential to get the best of the exposure, especially as you might want to pull shadows, with moving foliage you have no chance to bracket and have to expose to hold the highlights.

[OldRoy]

Thanks, Roy, for your helpful response.  I have used PTGui for about a year now and really like the program- especially the "control point" editor.  One thing that I haven't been able to do yet is get the "straighten panorama" feature to work (I get some kind of error).  Have you had this problem?  Mark, I don't mean to hijack your thread- maybe something will come out of this that will help us both.

John

Hi again John
I assume that you are trying to straighten a cylindrical pano rather than a spherical, by definition. If so I can't comment much as I don't do it very often. When I do I use the T1, T2 cp's (can't remember which is for horizontals and which for verticals) to level the panorama; I'm not clear what distinguishes this from "straightening". This involves selecting the same shot in both windows, the appropriate cp type and then adding one point on a nominally horizontal element in one window and setting the equivalent cp on another location on the same horizontal element (say, the horizon) in the other window. Then select "Align panorama" in the Project Assistant tab, then Edit in the new window, then "level". You probably already know this.

Like you I have had some problems with curvature in single row cylindrical panoramas (at least I imagine this is the issue you're addressing!) but I recall someone authoratitive saying that this was inherent in the medium - with an explanation why. As I best recall this was on the PTAssembler forum, which concentrates on non-spherical panoramas and is a source of good information. Ask someone there and you'll probably get an intelligent answer, unlike mine; however PTA is a competitor with PTGui so it may not be as welcome as on the www.panoguide.com forums - which I cannot praise too highly for the quality and helpfulness of its participants.
Roy
EDIT: Apologies for helping to drag this thread away from the OP's initial post.

[Panopeeper]

I created this stitching demo to illustrate the issue of "straightening".

Specifying horizontal lines is useful only in extremely few cases (with the open sea). Vertical lines are much more common, typically with buildings around.

Re banding in the sky: optical vignetting often causes problem (beside changing light or changing exposure between the frames, like with moving clouds). DPP, ACR have vignetting correction functions, I guess others have this too.

A polar filter can make life miserable.

[OldRoy]

Re banding in the sky: optical vignetting often causes problem (beside changing light or changing exposure between the frames, like with moving clouds). DPP, ACR have vignetting correction functions, I guess others have this too.

A polar filter can make life miserable.

I made the asumption that the shots use common w/b, exposure etc and that they are pre-processed for vignetting, ca etc. Having said that I have found that the blending applications do a remarkable job on disguising errors in the seams.
Roy

[button]

Thanks, everyone, for the help.  

John

[Ben Rubinstein]

I've found banding is a serious problem with stitching - IF you work with 8bit files. The stitching process involves a lot of messing with the files, especially when you need it to equalise exposure and as such given that the files have already been 'worked', the usual 8bit banding shows it's ugly head, often immediately but certainly the minute you try to apply layers, etc. I found this out the hard way, 16 bit is the answer.

[OldRoy]

I've found banding is a serious problem with stitching - IF you work with 8bit files. The stitching process involves a lot of messing with the files, especially when you need it to equalise exposure and as such given that the files have already been 'worked', the usual 8bit banding shows it's ugly head, often immediately but certainly the minute you try to apply layers, etc. I found this out the hard way, 16 bit is the answer.

I omitted this from my posts. I'm converting to 16 bit tiff too.

[MarkL]

That you can leave the software to equalise any exposure differences doesn't avoid the fact that you are not optimising the exposure, if it has to pull shadows then you are getting less detail and more noise. I usually stitch at iso 400 to freeze leaf movement with a polariser, ETTR is pretty essential to get the best of the exposure, especially as you might want to pull shadows, with moving foliage you have no chance to bracket and have to expose to hold the highlights.

Yes this is true. I have yet to have problems but the D700 at iso 200 is very low noise anyway.

However, since the area you are photographing each time is so small, the brightness range is usually very low and each frame is kind of 'optimised' by shooting in aperture priority, even if the entire scene has a very high brightness range.

[!--quoteo(post=0:date=:name=button)--][div class=\'quotetop\']QUOTE (button)[div class=\'quotemain\'][!--quotec--]One question I have for you, Mark: how do you deal with homogeneous blue sky at different exposures? Sky blending is pretty tough as is![/quote]

John, I have not had any problems with skies at all in CS3 even with the sun in the frame but have not tried a totally even blue sky. Splitting the row of frames at the horizon would help since the frames of sky will then all be exposed the same so it should be OK.