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View Full Version : Focus and Stabiliser whilst using tripod


rayton
3rd November 2015, 07:37 PM
Have just returned from a shoot and found many shots with unsatisfactory focus and sharpness. I was using autofocus and a tripod. I suspect the focus point moved to pick up on the wrong spots and I wonder if my setting was wrong for landscapes with lots of trees and branches? Also wonder if I should have switched off the image stabiliser whilst on the tripod?

DavyG
3rd November 2015, 07:47 PM
If using a tripod, I believe they recommend that IS be switched off.

It may be worth posting a couple of pics with the exif intact, you should be able to get some constructive advice then.

Dave

rayton
3rd November 2015, 07:57 PM
Thanks for the quick reply. Will switch IS off next time. Are there guidelines for posting images. Haven't done that before.

DavyG
3rd November 2015, 08:08 PM
Upload pics to the Gallery, then post link to image in the thread, this will then display the pic in the thread along with your questions.

Gallery page: http://e-group.uk.net/gallery/uploadphoto.php

Dave

PeterBirder
3rd November 2015, 09:04 PM
Hi.

You asked about using IS on a tripod in a post in February.;):)

To find out how to upload photos look at the site Homepage http://e-group.uk.net/ . On the right hand side you will see a section titled Video tutorials. These will show you how to upload photos to your free gallery space on the site and how to include photos in your posts.

Regards.*chr

rayton
3rd November 2015, 09:40 PM
Thanks Dave & Peter. I have upload an image & hope it shows what is required:
http://e-group.uk.net/gallery/data/508/Ford.jpg (http://e-group.uk.net/gallery/showphoto.php/photo/87457)



Ray

PeterBirder
4th November 2015, 12:14 AM
Thanks Dave & Peter. I have upload an image & hope it shows what is required:
http://e-group.uk.net/gallery/data/508/Ford.jpg (http://e-group.uk.net/gallery/showphoto.php/photo/87457)



Ray

Hi Ray.

I would say you have a combination of factors.

You used f18. With micro 4/3rds (and 4/3rds) format diffraction effects, which cause softening start to occur at apertures smaller than f8. At f18 they may be significant. I never close down more than f8. If you look at my recent thread http://e-group.uk.net/forum/showthread.php?t=39837 the first four shots were all at f8.

Your exposure time was 1.6 seconds. If there was any breeze there will be movement in the trees which will cause blur.

You had IS on using a tripod which as discussed before could be a problem.

Not sure what focus box(es) you used. I usually only use a single box. If you use all boxes or group of nine for this type of shot the camera will pick the box with the greatest contrast in it and it's pot luck whether this will be the point you want to focus on. If you look at the images on the camera before you delete them from the card you can view the INFO screens the second of which will show the actual focus box used for the shot. I haven't found any software yet that will display this part of the EXIF after you have downloaded the files.

Hope this helps.*chr

IanB
4th November 2015, 12:42 AM
I peter has it right; the photographer should pick the focus spot that suits the scene/subject. Generally the IS should be off when using a tripod however I haven't used my Oly with a tripod enough to know.
more important with longer lenses I believe

back off a stop or 3 from smallest aperture will give better files. Even canon L lenses require a back off

I'm starting to really appreciate the em1 focus peaking and when not using that I use single point focus and pick the focus point.

Ross the fiddler
4th November 2015, 06:34 AM
Hi Ray,
It would also be helpful (& desirable) to see your photos larger, at least 900 pixels wide (or even 1000 wide) & then we could see more detail & also appreciate the photos more too.

*chr

Kiwi Paul
4th November 2015, 06:34 AM
Thanks for the quick reply. Will switch IS off next time. Are there guidelines for posting images. Haven't done that before.

If you have a flickr account you can show images from there too, just select "BB Code" copy and paste into the thread on here.

Paul

rayton
4th November 2015, 06:42 AM
Many thanks for your helpful analysis Peter. I can certainly see that f8 works in your impressive images. Thanks to Peter for the extra supporting comments too. I will change my settings and technique as suggested. Afraid I am still shooting as in film days with SLRs when f22 for landscapes was normal. Unfortunately I deleted the images from the card after transfer to the computer. I was using matrix focus on my previous shoot which was trying to capture bird flight shots. Must remember to change settings for each type of shoot.

Kiwi Paul
4th November 2015, 06:50 AM
Many thanks for your helpful analysis Peter. I can certainly see that f8 works in your impressive images. Thanks to Peter for the extra supporting comments too. I will change my settings and technique as suggested. Afraid I am still shooting as in film days with SLRs when f22 for landscapes was normal. Unfortunately I deleted the images from the card after transfer to the computer. I was using matrix focus on my previous shoot which was trying to capture bird flight shots. Must remember to change settings for each type of shoot.

With touch screen cameras, when using a tripod often the easiest way to focus is to simply "touch" the part of the scene you want as the focus point, I do this with my GH-3, it's simple and effective.

Paul

rayton
4th November 2015, 06:56 AM
Thanks Ross for your suggestion on sizing. I thought there was a limit of 500 pixels on the longest side when uploading images here.
Paul, I have 'dabbled' with Flickr in the past but no longer have an active account. Will reconsider that.

Petanque
4th November 2015, 09:57 AM
Interesting thread this. IS on handheld or IS off with tripod, would the difference be significant? I am not sure. Using f5.6 to f8 for the type of shot the OP posted I have seen little difference. The benefit of IS is that you do not need to lug a tripod around, Macro and critical shooting aside. Peter, were your (superb) images handheld?

PeterBirder
4th November 2015, 10:35 AM
Thanks Ross for your suggestion on sizing. I thought there was a limit of 500 pixels on the longest side when uploading images here.
Paul, I have 'dabbled' with Flickr in the past but no longer have an active account. Will reconsider that.

Slight confusion between pixels and file size. 512Kb is the maximum file size and as Ross says 800 or 1000 pixels wide works well as many of us now have wide screen monitors. Having resized your image for the required pixel dimensions you need to adjust the compression (quality) of the JPEG to give a file size of less than 512Kb when you re-save it for upload.

Regards.*chr

PeterBirder
4th November 2015, 11:01 AM
Interesting thread this. IS on handheld or IS off with tripod, would the difference be significant? I am not sure. Using f5.6 to f8 for the type of shot the OP posted I have seen little difference. The benefit of IS is that you do not need to lug a tripod around, Macro and critical shooting aside. Peter, were your (superb) images handheld?

I think the Olympus IBIS, especially the 5 axis version obviates the need for a tripod except for very long exposures and the cases you quote. For the types of photography I do these days I never use a tripod. In fact my tripod is now only used for SWMBO's spotting scope.:)

Thanks for your kind comments. Yes those shots were all hand held as was the moon shot in this post http://e-group.uk.net/forum/showthread.php?t=39903 . The only extra thing I did for this shot was to lean my shoulder against the wall of the house to make me a bit more stable.:)

Regards.*chr

Jim Ford
4th November 2015, 11:07 AM
I've never been convinced by the explanations as to why you should shoot with IS off on a tripod.

I can't see any technical reason why the IS system should be 'confused' by the lack of motion of the camera on a tripod. If you're holding the camera in your hand and the IS senses motion, it will move the sensor to counteract the motion. If the IS doesn't sense motion because the camera is on a tripod, then it won't move the sensor. It seems to be quite technically straightforward.

Suppose you have extremely steady hands, or are leaning with your head against a wall or tree - does this count as a 'tripod' and you should switch the IS off?

Jim

Ross the fiddler
4th November 2015, 11:16 AM
I've never been convinced by the explanations as to why you should shoot with IS off on a tripod.

I can't see any technical reason why the IS system should be 'confused' by the lack of motion of the camera on a tripod. If you're holding the camera in your hand and the IS senses motion, it will move the sensor to counteract the motion. If the IS doesn't sense motion because the camera is on a tripod, then it won't move the sensor. It seems to be quite technically straightforward.

Suppose you have extremely steady hands, or are leaning with your head against a wall or tree - does this count as a 'tripod' and you should switch the IS off?

Jim

Previous models (E-30 DSLR) did show a difference if mounted on a tripod with IS on. I had an example (still in my gallery) of vertical over-correction when leaning my elbows on the table for a short distance shot. These later models (with 5 axis correction) don't seem to have anywhere near the same effect but it is still advisable to turn off IS if on a tripod so there isn't any chance of vibration over-correction. The other thing for tripod shots (usually) is to use 0 sec. AntiShock too (or shutter delay).

rayton
4th November 2015, 12:00 PM
Thanks Peter for the sizing info. Hadn't thought of increasing the jpeg compression.

Petanque, I also wonder if the difference could be seen between shooting IS on or off on a tripod. Have read that it doesn't make much difference. I wanted the tripod yesterday because of low light in dull overcast conditions. Didn't want to increase the ISO risking noise in the shadows. Will certainly open the aperture more in future and adjust the focus mode.

Petanque
4th November 2015, 12:15 PM
Hi Ray, That would be an interesting experiment, particularly as, like me you are using the e-m10 with 3 way IS. If your tripod is handy I would be interested in seeing the results. I am still learning about apertures and the various effects resulting from them but at the moment I try to work with f5.6 to f11. I use the 12-50, almost exclusively with my e-m10 and find working in aperture priority mode works best with this combination. Regards Gary.

Jim Ford
4th November 2015, 02:42 PM
it is still advisable to turn off IS if on a tripod so there isn't any chance of vibration over-correction.

But surely if the camera is on a solid tripod, then there is no vibrations and hence no overcorrection?

Jim

Jim Ford
4th November 2015, 02:48 PM
it is still advisable to turn off IS if on a tripod so there isn't any chance of vibration over-correction.

But surely if the camera is on a solid tripod, then there is no vibrations and hence no overcorrection?

Jim

Jim Ford
4th November 2015, 02:49 PM
Sorry about the triple post! The site just seemed to 'hang' for a minute or so.

rayton
4th November 2015, 03:24 PM
Gary, I didn't mean that I am experimenting with the tripod and IS. My tripod use is minimal these days so my main objective is to get the focus right and use wider apertures. Ray

Zuiko
4th November 2015, 04:43 PM
But surely if the camera is on a solid tripod, then there is no vibrations and hence no overcorrection?

Jim

The emphasis should be on solid tripod, a flimsy one can introduce more problems than it solves especially if there is a breeze and/or the centre column is fully extended, in which case the whole setup can vibrate like a giant tuning fork! Whatever the tripod, best practice is to set the camera to Anti-shock mode; I use a four second delay.

I can't comment with any certainty about the effects of using IS on a tripod, but as there seems to be some doubts about the wisdom of this I always turn it off just to be sure. :)

Jim Ford
4th November 2015, 05:47 PM
The emphasis should be on solid tripod, a flimsy one can introduce more problems than it solves especially if there is a breeze and/or the centre column is fully extended, in which case the whole setup can vibrate like a giant tuning fork! Whatever the tripod, best practice is to set the camera to Anti-shock mode; I use a four second delay.

I agree - I do similar and both my tripods are substantial.


I can't comment with any certainty about the effects of using IS on a tripod, but as there seems to be some doubts about the wisdom of this I always turn it off just to be sure. :)

I do the same, but am not sure whether I'm just supporting an urban myth. I'd like to know the engineering rationale behind it.

Jim

Kiwi Paul
4th November 2015, 06:05 PM
I think this is a case of suck and see.
It's easy to take a few photos of the same scene with IBIS on and then off when on a tripod, taking a few will ensure consistency.
This is a case where we can answer the issue ourselves, it may even depend on what focal length is used, what shutter speed etc so there may not be one conclusive answer.
As I've taken countless photos with IBIS off when on a tripod and always got good results I just turn it off now anyway. I have on occasions left it on and seem to recall when looking closely at the images on the PC a slight lack of sharpness on some of the images.

Paul

PeterBirder
4th November 2015, 07:43 PM
I do the same, but am not sure whether I'm just supporting an urban myth. I'd like to know the engineering rationale behind it.

Jim

It's not an urban myth.

The manual of every Olympus camera with IBIS to date contains a statement "When using a tripod, set [Image Stabilizer] to [OFF]".
Olympus designed the system so I'm happy to accept that they know what it does and does not do.

Daveart
4th November 2015, 10:59 PM
Hi I think the way Olympus have designed the image stabilizer is by frequency of movement by the human motion which produces a motion frequency very different to a frequency vibration produced by a support ie tripod, which means that it can assimilate the frequency more accurately, this is why Olympus IS is the best on the market.
So if on a tripod it is trying to correct the wrong frequency of movement so in effect introduces motion incorrectly, this can also occur with high shutter speeds above 1/1000th of a second.

But may have changed on 5 axis ibis which improved errors, I have inadvertently taken the odd photo on a tripod with ibis on with no difference in image quality than when
I realised it was on and then switched it off retaking the shot, and compared both, and with different focal lengths upto 300mm, with my em5.

mstphoto
4th November 2015, 11:38 PM
A large proportion of my images are tripod mounted with the IS set to Auto.
Not sure if this is the correct thing to do but it appears to work ok.
Also, it helps if I take a hand held shot and forget to switch the IS back on :rolleyes:

Mike

Jim Ford
4th November 2015, 11:50 PM
Hi I think the way Olympus have designed the image stabilizer is by frequency of movement by the human motion which produces a motion frequency very different to a frequency vibration produced by a support ie tripod, which means that it can assimilate the frequency more accurately, this is why Olympus IS is the best on the market.
So if on a tripod it is trying to correct the wrong frequency of movement so in effect introduces motion incorrectly, this can also occur with high shutter speeds above 1/1000th of a second.

Hmm - not sure how they could design a system that caters for the tremor characteristics for the whole range of human sizes, ages and shapes. I would think that the tremor characteristics of a (say) 16 year old 5ft 2ins 5st female would be totally different to that of a 30 year old 6ft 6ins 20st male. Is it suggested that the IS can cater for the very complex motions of body tremors, but not that of the simple motion of tripod vibration?

Jim

Zuiko
5th November 2015, 09:02 AM
Hmm - not sure how they could design a system that caters for the tremor characteristics for the whole range of human sizes, ages and shapes. I would think that the tremor characteristics of a (say) 16 year old 5ft 2ins 5st female would be totally different to that of a 30 year old 6ft 6ins 20st male. Is it suggested that the IS can cater for the very complex motions of body tremors, but not that of the simple motion of tripod vibration?

Jim

.......or someone riddled with Parkinson's. Yes, the range of variables is truly astonishing. I think it is far from clear why IS could be detrimental when the camera is on a tripod, but given that the opening poster is getting unacceptable results for reasons unknown it certainly makes sense for him to switch off IS in these circumstances, if only to eliminate it as a possible cause of the problem.