Keith Cooper

Keith Cooper

Lives in United Kingdom Leicester, United Kingdom
Works as a Commercial Pro Photographer
Joined on Feb 16, 2003
About me:

Lots of photography articles and reviews on the Northlight site - see the latest at:
http://www.northlight-images.co.uk/photography-articles-and-reviews/

My book: Using tilt/shift lenses
https://www.crowood.com/products/photography-with-tilt-and-shift-lenses-by-keith-cooper

My real work:
http://www.northlight-images.co.uk/commercial-photography/

Comments

Total: 162, showing: 1 – 20
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In reply to:

nhr5005: Perhaps a silly question, aside from the sunstar effect, does number of aperture blades affect sharpness?

Yes, slightly, but not in any obvious way for most uses I should imagine.
It's most obvious on any part of the image that isn't perfectly in focus, but I found the ease that specular reflections anywhere in the image produced star effects intruded more. It may look OK for a night shot, but when it's reflections of shiny bits in a room, it's less welcome.

Having used the 20mm and original 15mm at night on similar subjects I prefer the higher blade count if given the choice.

Link | Posted on Apr 11, 2022 at 16:35 UTC

This is a good move. I've recently been testing the new 20mm, following on from my original testing of the 15mm. [both covered in the 3rd party lens forum] The 15mm prominent spikes on light sources and impact on OOF areas were not my preferred look. Tolerable, but I'd go for the new version.

For the 15mm I simply don't share the gloom and despondency (YMMV) I see from some ;-)

BUT, as ever, I only had a single copy of each and can only comment that mine (20mm and 15mm) were sharp enough for me to happily use them in my architectural work.

Link | Posted on Apr 11, 2022 at 15:39 UTC as 8th comment | 1 reply
On article DPReview TV: Laowa 20mm F4 'Zero -D' Shift lens review (89 comments in total)
In reply to:

bdbender4: It would be good to see you guys do a video on the difference between a shift-only lens and a tilt-shift lens. The shift lens straightens out verticals and... what else? The tilt-shift is classically used for... what? I have read about the theory of tilt-shift but it would be good to see a video of one in actual use.

If you're interested in tilt, I've produced a series of short videos that go with my book about tilt shift lenses and their use.
This one shows the effect of tilt used at shorter distances quite well
https://www.northlight-images.co.uk/video-set-lens-for-close-up-tilt/

Link | Posted on Mar 29, 2022 at 21:12 UTC
In reply to:

Petka: How much need there is for shift lenses anymore, when stitching software has become as good as it is? I would think taking 4 shots (or maybe more) with a standard wide angle lens with similar focal length stitched and corrected would give the same or even slightly larger angle of view as this.

"Stitching does not remove misaligned lines"

Depends on how you process images - and what you mean by 'misaligned lines'

Link | Posted on Mar 29, 2022 at 17:26 UTC
On article DPReview TV: Laowa 20mm F4 'Zero -D' Shift lens review (89 comments in total)
In reply to:

dbateman: Please ask Loawa to make a F-mount to gfx, m43rds, E-mount, ete tilt adapter.
This would be the easiest way to add tilt to their 15mm and 20mm shift lenses which have a 65mm image circle and can cover the gfx sensor size with 8mm of shift.

F mount is probably the worst one to start from - the comparatively small diameter makes for significantly more physical vignetting concerns than a wide mount like Z. For adapters, the EF might be a better choice
A far bigger problem for myself is likely that this design is not optimised for any significant amount of tilt. If I'm paying for lens tilt I want it to work well - as ever YMMV, since I'm still happy to use tilted M645 lenses with a fotodiox adapter.

If tilt was offered I'd want some quality in the resulting images. Using the

Link | Posted on Mar 29, 2022 at 15:56 UTC
On article DPReview TV: Laowa 20mm F4 'Zero -D' Shift lens review (89 comments in total)
In reply to:

fpessolano: so apart from focal,in terms of optics quality which one is better 15 or 20?

Having tested examples of each one, the 20mm has slightly better image quality over the full image circle.
The 15 I tested had the 5 blade aperture. Personally I much prefer the 14 blade aperture of the 20. I simply don't want overly prominent sunstars
Examples at https://www.northlight-images.co.uk/review-laowa-20mm-shift-lens-f4/ and https://www.northlight-images.co.uk/review-laowa-15mm-f4_5-shift-lens/

Much like my TS-E24mm is 'better' than my TS-E17mm - apart from focal length issues... ;-)

Link | Posted on Mar 29, 2022 at 15:43 UTC
In reply to:

Petka: How much need there is for shift lenses anymore, when stitching software has become as good as it is? I would think taking 4 shots (or maybe more) with a standard wide angle lens with similar focal length stitched and corrected would give the same or even slightly larger angle of view as this.

Very useful for a single shifted shot - where things are moving

For multiple stitched shots - easy to do and you know the results from the shots on the camera

Shift for me is absolutely not about getting wider views (it's a part, but small part)

Link | Posted on Mar 29, 2022 at 14:23 UTC
On article DPReview TV: Laowa 20mm F4 'Zero -D' Shift lens review (89 comments in total)
In reply to:

Sergey Borachev: It should be obvious Laowa built this to a price and performance is therefore limited by that. Good fun for those who do not need the best professional quality and that's a good thing, as so many photographers simply do not have access and unable to enjoy this otherwise.

I use a TS-E17 and TS-E24 II 'professionally' and after using this lens for a few weeks, would happily take it with me on a paying job. Oh, wait - I'm using it on a job on Thursday ;-)

The fact that it's relatively cheap for such a lens is great from my POV, if it helps a few more people experience what you can do with such lenses.

Link | Posted on Mar 29, 2022 at 10:19 UTC
On article DPReview TV: Laowa 20mm F4 'Zero -D' Shift lens review (89 comments in total)
In reply to:

Jon555: On the one hand it's a shame it doesn't have Tilt as that is something that is nearly impossible to fake up in post. On the other hand every single person I've seen using a Tilt/Shift lens has only been using Shift (for paid architectural photography) and none I recall speaking to really knew how to use the Tilt.

I think 20mm is an excellent focal length choice too...

The stuff going on just below the Sunstars at 5:10 though, just wow !!!

I'd just note from my own testing of this lens (see the 3rd party lens forum) that the lens I had did not exhibit as much flare and mush.

Big caveat - as with DPR, I only had the one lens to test (RF mount, but same internal optics)

Link | Posted on Mar 29, 2022 at 10:13 UTC
On article DPReview TV: Laowa 20mm F4 'Zero -D' Shift lens review (89 comments in total)
In reply to:

Naveed Akhtar: How shift lens panorama differs from a panoramic tripod head panorama? or handheld one?
in both of these later cases you are moving the whole camera and lens. And then stitch it later in Photoshop

A left/right stitch, for example, gives a wide view that is a rectilinear projection - essentially a crop of a view shot on a much wider lens.
Stitching panned images gives a projection which is dependent on your stitching software - more control, but the final result is different to the viewfinder.

Using shift for wide panos needs care since image quality can drop off more in the shifted direction.

Link | Posted on Mar 29, 2022 at 10:11 UTC
In reply to:

Keith Cooper: I've got one here to test (RF mount version) and have some notes in the 3rd party lens forum
https://www.dpreview.com/forums/post/66041736

It's still with me, so if anyone has any specific questions, let me know?

The optics are identical in every mount - just the rear tube/mount bit changes...

Link | Posted on Mar 29, 2022 at 09:57 UTC
In reply to:

Lars V: What's the image circle?
Kinda relevant for a lens supporting multiple formats.

No need to adapt - there is a GFX version with ±8mm shift

Link | Posted on Mar 28, 2022 at 22:04 UTC
In reply to:

lococola: What is the difference between using a shift lens and correcting perspective in Camera Raw? No pixel transformation with a shift lens so no reduction in image quality?

With wider lenses, the correction becomes very noticeable with any significant amount of correction.
My main issue is the lack of knowing what's in the frame after software correction of any degree.

If I look at the Canon TS-E lenses I use, they are some of the best lenses I've got anyway.

The other thing is that using them a lot, shifts figures quite a lot in my shot visualisation. Combining panning with elements of left/right shift is still something I need to see on the screen/VF

One other thing - smart sharpening tools like sharpen AI work an absolute treat on shifted images - this really helped when I recently had an H6D 100C + HTS1.5 and 28mm here to test.

Link | Posted on Mar 28, 2022 at 20:49 UTC
In reply to:

derfotograf: Very impressive, even the image quality at the corners and margins. The 11 mm rise/fall and shift are equivalent to 45.8% of the image height in landscape orientation. Compared to my Rodenstock Apo Grandagon 4.5/45 mm with a 6x9 cm roll film back on my large format camera with only 33.3% of the image height (18 mm net), this lens is a must-have for me for simple assignments. I've checked the Phillip Reeve images and to be honest, the images you can make with this lens are truly amazing.

The lens holder wasn't available when I got the 20mm a few weeks ago for my testing/review. I've still got it here and have been told that the adapter will be sent to try.
Assuming it arrives, I'll start a thread in the 3rd party lens forum with info.

Link | Posted on Mar 28, 2022 at 20:08 UTC
In reply to:

lococola: What is the difference between using a shift lens and correcting perspective in Camera Raw? No pixel transformation with a shift lens so no reduction in image quality?

Mainly predictability of the end result. The more the shift the more difficult it becomes to estimate what's going to be lost and the final shape of the image. It's tricky with vertical shift , but once you us left/right or diagonal shift it's very difficult. Obviously changing the picture can scale/lose info.
I like being sure what I'm going to get - that and clients don't like images randomly cropped to different aspect ratios.

I was recently asked to do a webinar about tilt/shift by BenQ. I've edited/expanded the recording to cover what you can so with them. It's ~50mins but covers almost every aspect of use, and why
https://www.northlight-images.co.uk/tilt-shift-lens-use/

Link | Posted on Mar 28, 2022 at 20:05 UTC
In reply to:

Keith Cooper: I've got one here to test (RF mount version) and have some notes in the 3rd party lens forum
https://www.dpreview.com/forums/post/66041736

It's still with me, so if anyone has any specific questions, let me know?

The field of focus seems flatter than the 15mm I tested.

There is a distinct softening in the far corner if you shift diagonally, which is to be expected, but I noted no difficulties in focus.

A caveat though, I only have the one sample lens to test...
I'll post a few higher resolution images in the forum thread when I get a chance

Link | Posted on Mar 28, 2022 at 18:49 UTC
In reply to:

Mistral75: Why $1,299 when Venus Optics specify $1,099?

The price showing now is the one I was originally told when I got the lens a few months ago - then it went o the higher number and then back to what it is now.

Link | Posted on Mar 28, 2022 at 17:53 UTC
In reply to:

Trolly: Nice to see a lens released for DSLR these days. And Pentax included!

Yes, a shrewd move. This was always going to be a niche lens.
Great to make it more widely available for people to use.

I'm told the optics are identical for every mount option

Link | Posted on Mar 28, 2022 at 15:21 UTC
In reply to:

Trolly: 1 mm shift is very little. Must be incorrect.

±11mm on all mounts except Fuji G which has ±8mm

Link | Posted on Mar 28, 2022 at 13:13 UTC

I've got one here to test (RF mount version) and have some notes in the 3rd party lens forum
https://www.dpreview.com/forums/post/66041736

It's still with me, so if anyone has any specific questions, let me know?

Link | Posted on Mar 28, 2022 at 13:07 UTC as 26th comment | 8 replies
Total: 162, showing: 1 – 20
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