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-   -   LETUS35A-My Initial impressions and questions (https://www.dvinfo.net/forum/alternative-imaging-methods/53966-letus35a-my-initial-impressions-questions.html)

Madhav Yerella November 7th, 2005 01:14 PM

LETUS35A-My Initial impressions and questions
 
Hi All,
I got LETUS35A from Quyen and following are my initial impressions,
Quyen is a very nice guy and he has done fantastic work so far.

1)Had no probelms attaching to my panasonic GS400 camcorder with (43-52+52-58 step up rings) and NIKON SLR lens on the other side also fits fine.

2)I would say the design is very very intelligent with the kind of products that he used to build this adaptor.

3) The adaptor is a nice plug and play device and worked out of box.

That being said I have a few questions for Quyen and other experts.

1)The LETUS35A I got is for Nikon mount.I am using a Nikon SLR lens(AF Zoom-Nikkor 28-80mm f/3.5-5.6D lens) that comes with Nikon N65 SLR model, on this lens there is no manual f-stop or focus settings, I can only alter the focal length from 28-80 by rotating the lens.First thing I noticed is Outdoor works but indoor I just see black screen;indoor I can not get any inverted picture at all. Does that mean I can not use this lens for indoor? Any suggestions on lens that works both indoor and outdoor? Does anyone has this strange problem? Even for Outdoor I am not getting a satisfactory image of long distant objects with this lens?

2)One of the reasons I was using this lens is to get different shot sizes with out increasing/decreasing distance between camera and subject.If I use,say,Nikon 50 mm 1.4 lens,which is of fixed focal length, how can I get different shot sizes?

3)Also getting slight vignetting-I am using GS400 Camcorder-So what I did is zoomed in and captured slightly lesser area from the GG. So, in post I was seeing black bars on edges. And later I resampled it using Vegas,as though it captured 24X36 gg image. Do you guys think it will lose any resolution by my workaround.

Vignetting apart, which is a minor issue for me, Lens is the biggest obstacle for me at this point. Could you guys suggest some Nikon lens, as I have to stick with nikon because adaptor is Nikon mount and also GG distance is meant for Nikon lens.

Quyen Le November 7th, 2005 01:56 PM

1. I've heard that AF Nikon lenses will keep the aperture of the last shot using Nikon AF camera, if this is the case, you could change the aperture using the camera and play with it until you get the desired aperture. In this case, your lens is closing too much so indoor shooting doesn't see any light coming thru the lens.
2. Get more than 1 prime lens.
3. If you can still see black bar on the edges, you probably need to zoom in a little more. If the lens is too wide, it will give some vignetting,
Hope this helps. Thanks.

Quyen

Madhav Yerella November 7th, 2005 02:22 PM

Hi Quyen,
Thanks for your reply. I do not have an iota of doubt on LETUS35A. It's the LENS and getting the setup right is the issue here.
1)AF lens issue: Didn't quite get that. Which one is the suggestion you made a)Close and open the SLR lens cap every time to make it a new shot b)Change the aperture settings on GS400 Camcorder-I actually tried with fully opening the aperture also for indoor.
3) Vignetting: On Camcorder's LCD I am not seeing any blackbars, I zoomed in enough not to see any vignetting. When I import to Vegas, I saw it.It probably could be because of the import properties I set in Vegas. When I resampled the imported footage, the vignetting is gone. Am I doing right?
It's not actaully diagonal black bars on edges (vignetting) but horizontal and vertical ones, which tells me it's about the image size.

Quyen Le November 7th, 2005 03:47 PM

1. Put your lens on your camera, point to the dark area without using flash, try to take a picture then take the lens out, I think the lens now is wide open. at f3.5, you will lose about 3.5 stops, at f5.6, you will lose about 5 stops. That doesn't count any light loss by the adapter, so this lens probably not good for indoor without proper lighting.
3. The frame using on Letus35(A) is a litle bit larger than 24x36, so zoom in past the edge will give you close to 24x36 frame. Some camera, the LCD doesn't show the full image but rather crop the edges just like TV, so if you mount the adapter on and zoom in, try to use the computer and using capture mode to make sure the edges disappear, this will give you clean image. Thanks.

Quyen

Kyle Edwards November 7th, 2005 03:56 PM

That won't work. You have to keep the lens open by setting a pin back on the rear of the lens. Find a part that slides and put something in there to keep the iris open.

Steve Witt November 13th, 2005 02:17 PM

Hello Madhav Yerella,
I am about to receive a GS400 soon I am interested in these adapters. What are the set up rings that you are talking about...and is the LETUS35A
different from the LETUS35? I have only found one website on this product and I cant find LETUS35A or any set up rings like you mentioned. Could you please tell me where to look or more about what you have? Here is the only link that I have http://www.letus35.com/index.html

Brett A. Noe November 14th, 2005 09:52 AM

Probably the best advice is to use MF lenses with your 35mm adapter. My finfings have been that AF lenses just aren't worth the trouble.

Madhav Yerella November 14th, 2005 12:17 PM

Hi Quyen,
I have done some testing with Nikon 50mm 1.8 yesterday. I will send some footage tomorrow, it should reach you coming weekend.

Hi Steve,
1)Both Letus35 & Letus35A have same 58mm dia thread on one side. The dia on GS 400 is 43mm. So you need a step up ring to go from 43 to 58.I used 2 rings: one from 43-52 and second from 52 to 58.
2)Quyen says for LEtus35A there is one part different that he got from Surplusshed.

Hi Kyle,
I used small paper to push the lever to keep AF lens oris open. It worked but with AF lens everything is in foucs,there by not a sharp picture. Any suggestions for buying 3 prime lens?

HI Bret,
I am using Nikon 50mm 1.8.
1)I am planning to buy 28mm 2.8 and 100mm 2.8. Any suggestions?

Dan Diaconu November 14th, 2005 12:54 PM

here is an AF 1.8/85 Nikkor at work: (9seconds 2Mb)
http://dandiaconu.com/gallery/albums...p_in_frame.wmv

Madhav Yerella November 14th, 2005 02:02 PM

Hi Dan,
The clip is great.I know you have guided lot of people here at dvinfo.
I looked at the lens in google images,it has aperture and focus rings.How different,in your experience (as you had done lot of work and clips posted with every kind of equipment),is this lens from say MF prime 85mm 1.8 which too has aperture and focus rings.

I am on limited budget and would like to spend less than $150 on 2 lenses.
I can not get good shots say 30ft away with normal prime 50mm 1.8 MF nikon series E.That's my problem right now,and also the long shot doesn't give me details (for long shot I focus at infinity).

If I have to buy 2 lens, would you suggest MF 28mm 2.8 and MF 100 2.8

or 2 AF lenses of about same max aperture with aperture and focus rings.

Dan Diaconu November 14th, 2005 04:22 PM

Madhav,

I can only comment on the diff between AF and manual as I had them both.
The mechanics in the AF lenses are of latter generation. They move faster, the optics are of later generations as well (newer coatings) but the actual angular movement is way smaller than found on MF lenses (only 45 degrees as opposed to over 200 degrees) Focusing accuracy is more critical on AF lenses. A slight movement and the pic is soft. They are good but you have to practice a bit. Just as true, they will allow a focus change from close to far in no time (as you saw) which is a bit more difficult to achieve with MF. Also, on the same theme, most of the time you will need to "follow" the action not whack (cough, cough) rack the focus as seen.

Lens suggestions?...
Lens is something we don't buy every day.
This is an investment and a commitment. Instead of two so and so... get ONE only, but get the fastest lens you can afford now (1.4/50? 1.2/50?). Otherwise, you mess with them, they mess with you, in the end you end up frustrated, money is spent anyway but you are not as happy as you could be for the $. Do it RIGHT or don't do it at all.
You'll be happier to SEE quality and will INSPIRE you to DO and GIVE BACK quality.


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