NikonGear'23

Gear Talk => Lens Talk => Topic started by: Michael Erlewine on September 22, 2015, 20:19:20

Title: Venus Optics 15mm f/4 Wide-Angle 1:1 Macro Lens
Post by: Michael Erlewine on September 22, 2015, 20:19:20
Of course I always have to see for myself, or most of the time. A 15mm macro lens? Give me a break. Yes I had to try it, although everything I know about lenses was waving me off.

And yes, my instincts were correct. This is not an exceptional lens. In fact, it is a one-trick pony; nothing more. If you want to photograph a subject that literally is touching the front lens (or nearly), then this lens will do it. That’s the only good news. Well, it is pretty sharp in the center, but focusing the damn thing is nearly impossible. The focus throw is so small (about 90 degrees) that the tiniest movement is too much, and that makes focus stacking not a lot of fun. Keep in mind that the Leica 100mm f/2.8 APO Macro Elmarit-R has a focus-throw of some 720 degrees.

I could live with that (perhaps) or stick in on a focus rail, but the lack of correction negates whatever results I might get from the close-focus. It is sad. We need a really good lens that does what this lens promises to do, but physically can’t deliver.

Again, the bottom line for me is that the overall quality of the image (despite whatever “sharpness” we can derive from it) is just not good enough for prime time, at least for the kind of work I like to do.

I will probably keep playing with it, but I have already reached the breaking point into disappointment, so I am most likely sending it back. I would love an “ultra-wide macro lens,” but perhaps that term is an oxymoron.

Here are a few samples on the Nikon D810, but I did not take a lot of pains to make these, just enough to form an opinion, which I now have. Yes, I could make this lens work, sort of, if I really wanted to. Yet, since the only kind of photo it makes, the one-trick for this pony, is that ultra-close wide-angle shot, but, then, the image quality would always mostly suck.

Your thoughts?
Title: Re: Venus Optics 15mm f/4 Wide-Angle 1:1 Macro Lens
Post by: Fons Baerken on September 22, 2015, 20:30:53
reminds of a fisheye

you could probably do the same with wide angle lens plus K-1 ring

(https://c1.staticflickr.com/1/569/20730113754_50f4dcd12e_b.jpg)

the humble cv 20mm f/3.5 with k-1 ring stopped down,
the ir effect is my edit
Title: Re: Venus Optics 15mm f/4 Wide-Angle 1:1 Macro Lens
Post by: Bjørn Rørslett on September 22, 2015, 20:31:50
Why am I not surprised? These results are as I would expect from the design specification. Plus the short working distance is highly impractical and the attraction of a steep perspective quickly vanishes.
Title: Re: Venus Optics 15mm f/4 Wide-Angle 1:1 Macro Lens
Post by: Michael Erlewine on September 22, 2015, 20:52:22
Why am I not surprised? These results are as I would expect from the design specification. Plus the short working distance is highly impractical and the attraction of a steep perspective quickly vanishes.

I agree, of course. I just wanted to see for certain that this could-not or has-not been done.
Title: Re: Venus Optics 15mm f/4 Wide-Angle 1:1 Macro Lens
Post by: Michael Erlewine on September 22, 2015, 20:59:37
you could probably do the same with wide angle lens plus K-1 ring

Well, yes. I do that all the time, use the K-1 ring. However, in my experience the K-1 ring is still too much for wide-angle lenses at the range of 15-16mm, which is where I would like to be.
Title: Re: Venus Optics 15mm f/4 Wide-Angle 1:1 Macro Lens
Post by: Dr Klaus Schmitt on September 23, 2015, 08:55:20
Well, thanks for the efforts Michael, I am not very surprised either....
Title: Re: Venus Optics 15mm f/4 Wide-Angle 1:1 Macro Lens
Post by: Erik Lund on September 23, 2015, 09:03:46
Thanks Michael, actually some really nice sample images imho!

So we need to design a Short-K1... something to look at during our next workshop...  :D
Title: Re: Venus Optics 15mm f/4 Wide-Angle 1:1 Macro Lens
Post by: Bjørn Rørslett on September 23, 2015, 09:19:56
K-1 is physically about as narrow as the F mount bayonet design will allow - provided there are to be male and female mounts on the same ring. So any narrower and one needs actually to modify the bayonet of the host lens itself. Someone (Erik?) earlier suggested using a Leitax "F" mount for the Leica R lenses, which will add about 1 mm of extension if fitted to a standard F-mount lens. One presumably could shim that to get 1-2 mm additional extension. However, the functionality of the host lens (aperture control etc.) might be lost due to the non-standard interface.

To put all this into perspective, the depth of field will not be large when even this tiny amount of extension is added, because the determinant here is magnification of detail (smaller aperture increases depth of field, but not by much in such cases) . Thus all that is gained is a steep perspective and an inconveniently short working distance. A focal length of 15 mm is still way too long for the significant influence of the perceived depth of field.
Title: Re: Venus Optics 15mm f/4 Wide-Angle 1:1 Macro Lens
Post by: Erik Lund on September 23, 2015, 09:28:55
It was Andreas I belive with the Leitax mount... :)

Please bring along a K1 Bjørn and lets see what we can figure out... I was thinking of using it on a 15mm... but also unsure how well the 15mm works up close... maybe waste of time ::)
Title: Re: Venus Optics 15mm f/4 Wide-Angle 1:1 Macro Lens
Post by: Bjørn Rørslett on September 23, 2015, 09:32:24
Sure, I'll add another K-1 to my already overflowing bag :D

Also added a couple of F mounts with varying thickness, for experimental purposes.
Title: Re: Venus Optics 15mm f/4 Wide-Angle 1:1 Macro Lens
Post by: Erik Lund on September 23, 2015, 09:42:02
I know the situation  :D

What might be possible is to remove the middle part of the K1 ring where the locking pin and locking groove is located, this will shave off 3 or 4 mm out of the 5.8mm

The rear most part of the lens F mount bayonet will actually touch or align with the front surface of the Camera F mount...

The two halves of the Short-K1 should be soldered together after surgey.
Title: Re: Venus Optics 15mm f/4 Wide-Angle 1:1 Macro Lens
Post by: Frank Fremerey on September 23, 2015, 10:17:39
I asked for experiences with that lens a while ago and I am greatful that you, Michael, did test it now.

The best lens I had so far for wide view single shot macro (super steep shot) was the ZF 2.8/25 Distagon. It was also superb optical and the built quality was very fine too.

I keep a close eye on your developments. I intend to use the 1.4/24G more in the near field. Till now I was not able to produce the results that came to my mind when I first bought the lens. Architecture suits it very well, the near field is not its best field I feel.
Title: Re: Venus Optics 15mm f/4 Wide-Angle 1:1 Macro Lens
Post by: Michael Erlewine on September 23, 2015, 10:57:06
What might be possible is to remove the middle part of the K1 ring where the locking pin and locking groove is located, this will shave off 3 or 4 mm out of the 5.8mm

The rear most part of the lens F mount bayonet will actually touch or align with the front surface of the Camera F mount...

The two halves of the Short-K1 should be soldered together after surgey.

Hey Guys! Please make me one, if you can, and charge me for it. I have extra K-1 rings, so I could send a replacement.
Title: Re: Venus Optics 15mm f/4 Wide-Angle 1:1 Macro Lens
Post by: Erik Lund on September 23, 2015, 15:44:50
The idea looks nice and I remember having taken a K1 apart before and given up,,, but this time we will cut it and take out the middle part and see what actually happens with regard to interference issues, might be lenses with CPU and aperture lever etc will give us headache 😉

If we succeed we could make a few extra naturally! JA will make a spreadsheet covering the various costs as usual 😲😉

The concept looks ok on my sketches,,, but let's wait and see 😊
Title: Re: Venus Optics 15mm f/4 Wide-Angle 1:1 Macro Lens
Post by: Michael Erlewine on September 23, 2015, 16:50:37
Well, I would really love one and put it to good use, so please keep me in the loop.
Title: Re: Venus Optics 15mm f/4 Wide-Angle 1:1 Macro Lens
Post by: Erik Lund on September 23, 2015, 17:23:59
Please follow this thread
http://nikongear.net/revival/index.php/topic,1595.msg16942/topicseen.html#new
😊
Title: Re: Venus Optics 15mm f/4 Wide-Angle 1:1 Macro Lens
Post by: Erik Lund on October 01, 2015, 19:19:45
Never had time to write during the workshop so here goes;
I got about one millimeter shaved off and did a test assembly that show about further only half a millimeter more can be obtained in thickness.
Not much.
The design of the K1 really is about as much as is sanely possible ;) Nikon did a fine job originally.

Also please don't use a chipped K1 ring for lenses or extension rings with aperture leavers as the leaver will push directly into the CPU contact block!!!
Use any other (longer) extension ring for the CPU  like PK11A E3 etc.
A Short-K1 will be same problem,,,
Title: Re: Venus Optics 15mm f/4 Wide-Angle 1:1 Macro Lens
Post by: Björn Carlén on October 01, 2015, 19:42:37
Where can I find a K-1 ring? The shortest extension I have is PK-11.
Title: Re: Venus Optics 15mm f/4 Wide-Angle 1:1 Macro Lens
Post by: Michael Erlewine on October 01, 2015, 20:18:52

The design of the K1 really is about as much as is sanely possible ;) Nikon did a fine job originally.

That's what I wondered about. Thanks very much for making the effort!
Title: Re: Venus Optics 15mm f/4 Wide-Angle 1:1 Macro Lens
Post by: Bjørn J on October 01, 2015, 21:48:56
Where can I find a K-1 ring? The shortest extension I have is PK-11.

ebay is your friend. You can get only the K-1, or the whole set with K-1, K-2, K-3, K-4 and K-5:
http://www.ebay.com/sch/i.html?_from=R40&_trksid=p2050601.m570.l1313.TR0.TRC0.H0.Xnikon+k-1.TRS0&_nkw=nikon+k-1&_sacat=0
Title: Re: Venus Optics 15mm f/4 Wide-Angle 1:1 Macro Lens
Post by: Jan Anne on October 02, 2015, 14:10:11
You guys are so cute for trying to solve these kind of DLSR specific issues, I simply bought the Voigtlander Close Focus VM to Sony E adapter with a built in 4mm focussing helicoid  ;)

Worked pretty good with the Voigtlander 15/4.5 LTM in France a few days ago:
(https://c1.staticflickr.com/1/747/21869394652_955ba7791f_o.jpg)
Sony a7S with Voigtlander 15/4.5 LTM & Voigtlander Close Focus Adapter

(https://c1.staticflickr.com/1/731/21633272189_c9cbc1a530_c.jpg)
Sony a7S with Voigtlander 15/4.5 LTM & Voigtlander Close Focus Adapter
Title: Re: Venus Optics 15mm f/4 Wide-Angle 1:1 Macro Lens
Post by: Björn Carlén on October 02, 2015, 19:19:15
ebay is your friend. You can get only the K-1, or the whole set with K-1, K-2, K-3, K-4 and K-5:
http://www.ebay.com/sch/i.html?_from=R40&_trksid=p2050601.m570.l1313.TR0.TRC0.H0.Xnikon+k-1.TRS0&_nkw=nikon+k-1&_sacat=0
Thank you very much, Bjørn J! I just ordered the whole set.
Title: Re: Venus Optics 15mm f/4 Wide-Angle 1:1 Macro Lens
Post by: Bjørn Rørslett on October 02, 2015, 19:24:37
Having a K-ring set (or - preferably - several) is akin to fooling around with Lego bricks. For adults of course. But notwithstanding that caveat, they are so versatile and can be used for a surprising number of photographic applications. Extension tubes, spacers for allowing bellows to mount on modern DSLRs, acting as sun shades, makeshift adaptors for exotic lenses, quick-release filter holders (K2 plus K3), getting close-ups for wide angle lenses (Nikkor 20/3.5 + K-1 is a classic), etc. etc.

I must have acquired around 25-30 of these sets over the years.
Title: Re: Venus Optics 15mm f/4 Wide-Angle 1:1 Macro Lens
Post by: Björn Carlén on October 02, 2015, 23:01:35
Having a K-ring set (or - preferably - several) is akin to fooling around with Lego bricks. For adults of course. But notwithstanding that caveat, they are so versatile and can be used for a surprising number of photographic applications. Extension tubes, spacers for allowing bellows to mount on modern DSLRs, acting as sun shades, makeshift adaptors for exotic lenses, quick-release filter holders (K2 plus K3), getting close-ups for wide angle lenses (Nikkor 20/3.5 + K-1 is a classic), etc. etc.

I must have acquired around 25-30 of these sets over the years.
Sounds very interesting. I want to try the K-1 on my old Nikkors 28/2, 24/2.8 and 20/2.8. How to use the rings as sun shades I don't understand, though.
Title: Re: Venus Optics 15mm f/4 Wide-Angle 1:1 Macro Lens
Post by: Bjørn J on October 03, 2015, 00:04:02
The K-1 can also give some interesting results on the Nikkor 16mm/3,5:

Title: Re: Venus Optics 15mm f/4 Wide-Angle 1:1 Macro Lens
Post by: Björn Carlén on October 03, 2015, 00:10:40
The K-1 can also give some interesting results on the Nikkor 16mm/3,5:
Very nice!
Title: Re: Venus Optics 15mm f/4 Wide-Angle 1:1 Macro Lens
Post by: Bjørn Rørslett on October 03, 2015, 00:14:07
Sun shade? Easy. K4 and/or K5 have 52 mm threads. Just screw one or more rings into the front threads of a 52 mm threaded lens. Works with lenses from 50 mm upwards.
Title: Re: Venus Optics 15mm f/4 Wide-Angle 1:1 Macro Lens
Post by: Bjørn J on October 03, 2015, 00:24:14
Very nice!
Thanks. I have also tried the K-1 on a Zeiss 21mm/2,8 - seems to work great!
Title: Re: Venus Optics 15mm f/4 Wide-Angle 1:1 Macro Lens
Post by: Björn Carlén on October 03, 2015, 00:30:48
Sun shade? Easy. K4 and/or K5 have 52 mm threads. Just screw one or more rings into the front threads of a 52 mm threaded lens. Works with lenses from 50 mm upwards.
I'm eagerly awaiting the shipment from KEH.