Littel review of the Schneider Apo Digitar XL 28 mm 5,6/28 mm with modern Phase one back

[Alkibiades]

Little review on Apo Digitar xl 28 mm in combination with modern backs.

After I purchased Schneider Apo Digitar xl 28 mm here on Getdpi I get a lot of questions from members about my experiences with this lens and how this lens perform with some newer backs.
As we know the lens is easy to use with the older backs that share sensors like the 60 MP from Dalsa that is build in Phase one 160/260 and similar hasseblad and leaf backs. Also older 39 and 50 MP sensors from Kodak work very well with this lens.
These are all digital sensors that dont use micro lenses.
As we know the mirco lenses increase the color cast of wide angle lenses very much.
28xl as all wide lenses with symetrical lens designs are placed very close to the sensor, so even small movements wil produce a very strong color cast. Software like Capture one and Phocus can correct it till some point, from where the correction dont work well and a decrease in the saturation of the colors become visible.
This happens with following Dalsa big 80 MP backs (40,5 x 50 mm) as the little (33 x 44 mm) 40 MP.
With the Sony Cmos sensors the pixes destiny grows, so the color cast problematic did not bekome easier.
The sony 100 mp and the little 50 mp has the same problems and first with the new back illuninated 150 mp sensor the color cast problem could be resolved. so for this new sensors the 28 xl shoulde be again an atractive lens. becouse of the extremly high price of the 150 back I wish phse one and hasselblad will infroduce some day a new generation of the 33x44 backs with the new 100 mp sensor that is used already in Fufi GFX cameras.
So 100 MP back illuminated sensor in combination with the 28xl would be a dream team for me.
The reason for me is the symmetrical lens design of schneider lenses, that is ideal for architecture work- it is a dream to get no dsisortion without any software correction.
Afcorse are the Rodenstock Digaron-S and W great lenses, easy to use and even very well corrected but becouse of they optical design not really free of distorsion.
And for somebody like me who like to use Apo Digitars 43,47 and 60 xl mm the 28 xl would make the Schneider-line complete.

 

[Alkibiades]

This is an example for a simple architecture shots that I have already done with Digaron-w 32.
Even the results were superior, always some correction of distortion were necessary.
Here with 28xl no software correction of the distortion is needed.

 

[Alkibiades]

what I can say the sharpness of this lens is even wide open amazing. At Aperture 8 you get the best resolution, sometimes you need to stop down to 11 and the sharpness stay no this level.
The corner sharpness is also great, much better than it was with 35xl.
The 28xl is the only one wide angle lens from Schneider that have 10 lens elements instead of classic 8 lenses design. This additional correction make the lens really special.
The color cast is strong, but Capture one can handle the correction wery well.
here some additional pics made by walking around...

 

[Alkibiades]

what about extem movements?
here 25 mm, more is not possible on my Cambo wrs...

 

[Alkibiades]

the color cast was really extreme, there is some decrease of color saturation- I can see it becouse i know what it would be possible, but if the picture would be printed I dont believe that the viewer could recognise it. Also some decrease of sharpness can be recognise, but no other so wide lens could handle 25 mm movement...

 

[Alkibiades]

here a direct comparison with Digaron-S 23 mm..

 

[4x5Australian]

Alkibiades, thank you for your little review of the 28XL. Which digital back are you using here? Is it the IQ4-150?

 

[Alkibiades]

Alkibiades, thank you for your little review of the 28XL. Which digital back are you using here? Is it the IQ4-150?

Sorry, I forgot to mention:
I used Phase one IQ250 with 50 MP. This is usually not the best sensor for using the 28xl becouse it produce a very strong color shift. The Sony 50 MP is the most common sensor now becouse of the atractive price. the 100MP will have similar behavior beiing the large version of the same sensor.
So it is not the best combo but usable. I hope for a newer 100 sensor in 33x44 size comming soon: that solve all the color cast problematic.
The IQ4-150 is a dream- but too expensive for me- should work great with 28xl.
The sharpness of the 28 xl is amazing and should be great on IQ4-150.
I found the 28xl on my back little sharper than my Digaron-S 23 mm and on the same level like Digaron-S 35 and Digaron-W 32 mm (both lenses are the sharpest wide angle lenses that I tested).

 

[P. Chong]

Thanks for sharing.

 

[usm]

The 28xl will work on the CFVII50C?
Thanks for sharing this!

 

[Alkibiades]

The 28xl will work on the CFVII50C?
Thanks for sharing this!

The sensors are the same so it should work. But you will get a strong color cast at movements, Capture one can handle it well, the question is how effective is the ccast correction in Phocus.
Anyway the best option for your back would be Digaron-S 28 or 35 mm. with them you will not have CCast problems...

 

[diggles]

Hey Alkibiades,

Are you using the center filter with the 28xl in your tests?

Thanks!
Warren

 

[Alkibiades]

Hey Alkibiades,

Are you using the center filter with the 28xl in your tests?

Thanks!
Warren

no. I dont use the centerfilter.
I have one that is not the original but the IVa with an adapter- this was recommended by Schneider as the original centerfilter is not available any more.
But i dont use it becouse the big surface of the centerfilter is problematic in some difficult light situations: you get a big milky spott in the center that cant be corrected.
anyway in controlled light the centerfilter can be used, but capture one can clear LCC pretty well (when the movements are not used to the extreme) without using the center filter.

 

[sunhouwang]

Have you compared it with hr digaron-s 28mm?

 

[guphotography]

Have you compared it with hr digaron-s 28mm?

I have compared it with digaron s 28mm with help from Richard at Cambo. SK28 is noticeably sharper, from centre to edge, plus it has larger image circle, 90mm vs 70mm.

 

[Alkibiades]

Have you compared it with hr digaron-s 28mm?

not compared directly but i ownded 2 copies of the 28 HR.
the advantage of the 28 hr is that the lens can be used with all backs, there are no big color cast problems that cant be removed and the image circle if big enough for 33x44 mm backs. the sharpness is very high, similar to the 28xl, when there is a difference than a very small. maybe the 28xl is a bit sharper. the performance at the edges was OK but not as good as the 23 HR. even these lenses have similar lens design, the later produced 23 hr has a improved design that can be seen at the edges clear. 28 hr has afcourse some distortion, as all hr lenses. here is the 28 xl simply the better lens.

 

[cuida1991]

anyone compared 32 hr and 28 xl? Which one is sharper?

 

[mristuccia]

anyone compared 32 hr and 28 xl? Which one is sharper?

Quoting here below the OP message of Dec 1, 2021 on this very same thread:

I found the 28xl on my back little sharper than my Digaron-S 23 mm and on the same level like Digaron-S 35 and Digaron-W 32 mm (both lenses are the sharpest wide angle lenses that I tested).

 

[Paul Spinnler]

The 28 XL is extremely sharp, its SK's last and finest super complex wide angle, built for a next-gen of digital backs back in the day. Unfortunately, the design didn't gel with 80 MPX CCDs and then SK exited only for the lens to get a new life with the backside CMOS tech which made it useable even without CF.

What's even more impressive, is that it comes in fully rectilinear and has 90 IC at 28mm, ie it is the widest available MFD lens with such a large IC.

An optical masterpiece which will never be replicated – it was already back in the day more of a show piece for SK of what they can do and would not be economical in any way to do nowadays anew. Not in terms of R&D and not in terms of end price which would be beyond 10k at this stage, more like 13k seeing current new Rodie prices.

Its moot to compare the 32, 28 and 35 – they are all excellent; but again: there's no 90mm IC 28mm - its unique.

I personally always felt that the 28 XL is almost a tiny bit sharper at the centre than the Rodies and SK in the press release of the day also mentioned that it delevers high contrast 80lp / mm which I'd interpret as above 50% contrast in the centre for that resolution which is extremely impressive considering it is a 28mm rectilinear lens.

I mean just look at the distortion free UWA shots above from Alkibiades.

Spectacular.

 

[Alkibiades]

anyone compared 32 hr and 28 xl? Which one is sharper?

both lenses are very sharp, there will be no really visible differences in the sharpness between these lenses.
The main advantage of the 32 HR is the possibility to perform very well with all backs, without any exception.
It is the wide angle king of large chips, there is no real competitor there.
If you want the sharpest lens here so 35 HR will be the one. It is a little sharper, but has smaller IC afcourse. It has much less distortion also. 32 HR distortion need a software correction- no problem when you use C1.
the main advantage of the 28xl is the total different look, becouse of the symmetrical lens design. no distortion is simply impressive. also the very special aspect at this lens is the very special lens design, that is different to all lenses that Schneider ever done. The lensdesign is very special. Therefore the lens has not the weakness of the classic Biogon design, that are the weekness at the edges. 28xl is very sharp even at the last edge.
The weekness will be the strong light fallof that must be corrected and afcourse the fact that this lens cant be use with all backs becouse of the strong Ccast.
When I compared some pics made with32 hr and 28xl I could see sometimes better details ( clearer, sharper) at infinity with the 28xl. But sometimes it could be the focusing also. This could be seen at some landscapes. I shot also some architecture stuff to compare details, but there is no real winner. The theoretical resolution of the 32 hr should be higher.
Anyway the 32hr is the work horse for any use, the 28 xl is the special one that need a back that can support its value.
I hope there will be some new backs in the future with the new Sony BI sensors that have not the issues of the hasselbad 100c back.