Focus Bracketing (NO RAILS)

mjkzz · Post by **mjkzz** » Thu Jul 05, 2018 6:29 am

I have wanted to do this ever since I got the GH5 and later GX85, so I went and got a Leica 45mm Elmarit macro lens and put it on my GX85, tried the Focus Bracket function of the GX85, it turns out not bad at all. NO RAIL!!!

So maybe, this setup could be a good choice for field work or for low magnification work, it is simple, easy to set up, relatively cheap, compact, the final stacked quality is pretty good. Since I do not see a lot images done with this method, I gotta be missing something.

Is there such thing as "effective magnification"? The lens is 1:1 macro but the wasp filled up the frame (17mm wide), it would take 2x magnification to fill the frame on a full frame camera.

This was done with focus bracketing, 200 images at +3 step forward (0/+3), full electronic shutter with continuous light.

mawyatt · Post by **mawyatt** » Thu Jul 05, 2018 7:23 am

Geeze Peter, so all this $ I've spent on rails is not necessary

Nice work & image

Best,

Beatsy · Post by **Beatsy** » Thu Jul 05, 2018 8:09 am

Nice result.

Ref the magnification. Did you have the camera set in a APS-C crop mode? Or perhaps the camera crops to APS-C size to allow for alignment after stacking. Was it stacked in camera?

That's the one thing I find very frustrating with Sony. Love the cameras and IQ of the sensors (A7rii and A9), but Sony refuse to update firmware with new features (like Fuji do) and only address niggly concerns or bugs. This would be a wonderful feature for field stacking and well within the capabilities of the Sony h/w with an AF lens attached. On the A9, 20fps RAW with no blackout would be awesome for v. quick capture of short stack frames. But I'd rather just get the resultant RAWs and stack them externally than only get a final stack done by the camera.

ray_parkhurst · Post by **ray_parkhurst** » Thu Jul 05, 2018 9:20 am

For field work seems very good, though that is an $800 lens retail, so not a cheap solution.

mjkzz · Post by **mjkzz** » Thu Jul 05, 2018 4:30 pm

hahaha, Mike, your investment in rails are still sound as I do not see this method go beyond 2x

mjkzz · Post by **mjkzz** » Thu Jul 05, 2018 4:38 pm

@Beatsy, GX85 is a micro 4/3 camera, its sensor size is small, 17x14, it has a feature called focus bracketing where the camera will start shooting # of images you specified and move the focus by certain step size (again, you can specify it) till all images are captured.

The image was stacked in Zerene (of course), not in camera, though GX85 can do it in camera, I really doubt it can process 200 images in reasonable time and at reasonable quality.

I think Magic Lantern on Canon can do this, too, not very sure about Sony. I do hear that third party can develop Sony apps, for example for timelapse. So, maybe some day, such app will turn up.

mjkzz · Post by **mjkzz** » Thu Jul 05, 2018 4:40 pm

ray_parkhurst wrote:For field work seems very good, though that is an $800 lens retail, so not a cheap solution.

well, compared with a good rail and complicated setup gears, this is probably good one. I do think tripod is required as I can not hold the camera still for 200 images or about 1 minute.

RobertOToole · Post by **RobertOToole** » Thu Jul 05, 2018 9:14 pm

Well Peter, I'm impressed !

Thanks for sharing that.

Lou Jost · Post by **Lou Jost** » Fri Jul 06, 2018 7:09 am

mjkzz, this is my favorite method of stacking, since it is so fast. A few weeks ago I generated 100 Gb of images in just two or three days! There's no strict magnification limit to the method; you can use the same lens reversed, with a home-made adapter, to reach beyond 1x on the sensor. The trouble with higher magnifications is that the maximum total depth of the stacks gets shallower with increasing m. But some forum members have stacked stacks of stacks, moving the camera by rail between automated focusing stacks.

mjkzz · Post by **mjkzz** » Mon Jul 09, 2018 10:51 pm

Lou, I did put a Raynox 250 on the 45mm macro, I did not get any good results, image is too soft. But I will try again since this is the first time I am doing it.

Regards
Peter

Lou Jost · Post by **Lou Jost** » Tue Jul 10, 2018 4:51 am

I'm sure it depends on the lens used. For the photos at the link I gave above, I had used a 90mm Tokina macro lens.

Do try reversing your macro lens and making an automatic adapter to get above 1x on the sensor. MFT lenses are supposed to be nearly telecentric on the image side, so maybe you can achieve telecentricity without any add-on Raynox lens.