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GL Optics Sigma 18-35 Rehoused - Group Buy

David Kellermann

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I'm in contact with Nan from GL optics for several months now because of a group buy of rehoused Leica lenses (have a look at this thread).

Nan wrote me today a mail that he's also offering now a rehoused version of the popular Sigma 18-35. Here are some specs of it:

1) Sigma 18-35mm F1.8 Lens base;
2) 6063 Aluminum Rehoused Lens body;
3) Stainless interchangeable steel PL / Canon / Nikon mount;
4) 0.8 module gears;
5) New re-designed Lens focus/zoom/ aperture system to get the longer rotation compared to the original condition:
120 degrees focus throw for the regular rehouse, 300 degrees for the extended version for an extra fee of 850USD
6) 95mm front diameter;
7) Weight: 1.5 KG

Given that so many reduser want to get this lens, I asked him whether he might be interested in doing a group buy on it and he agreed.

I'll post his offer later password encrypted on my blog, like I did for the steadicam and slider group buy (the slider group buy is still open, by the way).

Send me a pm if you're interested in the group buy to get the password for my blog.

Cheers
David

UPDATE #1:

Nan just answered most of the questions:

1) How big is the focus pull (in degrees)?

It's about 120 degree focus rotation for the standard version and 300 degrees for the extended version

2) What's the real T stop of the lens? Could you mark the T-stops on the lens instead the f-stops?


3) Which image circle is covered (at 18mm and at 35mm). Will they cover the 5k Mysterium-X sensor or even the 6k Dragon sensor?

It will cover 5K sensor without problem. You will see the footage later. I have no 6K dragon, so I don't know it will cover or not.

4) If we order ~20 lenses, how fast could you ship them?

I think I can offer 20 Lenses within 5 weeks. maybe earlier:) But there is IBC 2013 at September, So 5 weeks is OK I think.

5) Will the lens keep focus when zooming?

Of course the Lens will hold on the focus when you zoom it.

6) How is the breathing?

I don't change the optical designed. So the breath will not change compare to the original condition.

7) Could you do some test videos incl. focus pulls and zooms?

Yes, you will find the test footage later.

8) Other than PL and Canon mount, would also be a Nikon mount possible? Are the PL and Canon mount user replaceable?

Depends one the order's number. If there are many orders of Nikon mount, I think I can make it. But I can't offer the replace Mount version now. Because it's very hard to hold on the focus on the Zoom Lens. If I offer the replace mount version, I think it maybe will has INF issue...

And, most importantly, here's the price (it's a public offer, so it's not password protected this time):

For 0-25 Lenses, the price is 3200 USD for lens + 80 USD for the cost delivery = 3280 USD.
For 25-50 units, I can offer 3000 USD for Lens + 80 USD cost delivery.
For more than 50 units, the price will be 2800 USD + 80 USD cost delivery.

850USD extra for a 300 degree focus throw

UPDATE #2:

you can start ordering the GL optics rehoused Sigma 18-35 T1.8 now. If you have already announced that you want to place an order... don't worry, you're registered for the first lenses :) Still, please send me the needed information.

The 120 degree version lenses will ship late September to October, followed by the 300 degree version.

How the group buy works:

1) Send me or an email with the following information:

Real name / Company name; REDuser name; Contact email address; Paypal email address; Invoice address; Shipping address; Phone number; Mount(s) of choice (PL / Canon / Nikon); Scale of choice (imperial or metric); focus (120° / 300°); Amount of lenses; Deposit (yes/no);

2) I'll collect all the orders and send them to Nan at GL optics.

3) Deadline for this group buy is September 22th midnight PDT.

4) GL optics will send you an invoice on Paypal after September 22th. The price depends on the number of ordered lenses. Shipment (80USD) is included in the price:

0-25 units = 3280 USD per lens
25-50 units = 3080 USD per lens
>50 units = 2880 USD per lens

5) There's also the option of a non-refundable deposit of 700USD. Since Nan can't be sure if some orders get canceled, and his funds are limited (well who doesn't have this problem), he can't start working on making the lenses before September 23th, when he sends out the invoices. So the option is that you make a non-refundable down payment and get in return one of the first delivered lenses.

6) Nan starts working on them soon, so the first lenses will be shipped in late September. If you order just before the deadline, you get your lens ~ mid / late November.

Again, you wont get charged before September 23th (unless you choose the deposit option). Paypal offers a money back guarantee, if the order is not fulfilled.

Please don't send me a conditional order like: "I'll order one, if we get more than 50 orders." You can send me always a message and ask how many orders are in, so that you can decide for yourself if you want to place an order or not.

Cheers
David

Phil.. you are getting pretty good at this. spot on.

Finally got a bunch of them in today. First thing you need to do is loose the janky hood..

6K HD fine. 6K full goes away about 20mm.

Should have it characterized very soon.

Update:

You can choose to pay 850USD more to get a 300 degree focus throw version!

Update:

Nan showed me at IBC the new interchangeable mount system for the Sigma lens.

There are no additional costs. You can decide if you want additional mounts (PL/Canon/Nikon). Every additional mount costs in the group buy 300USD, with a regular price of 350USD.

But there's a downside. Every mount has to be matched to the lens. So if you want later to get an extra mount, you would have to send the lens to GL optics.

Update:

Avi Cohen just posted a cool test video he did with the GL optics 18-35 (and some other lenses rehoused by Nan):

GL Optics Vs Avi Cohen - Sigma 18-35mm f1.8 TEST

 

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If this is Canon mount Im in!
 
If it's Canon mount I am in. Pl, still a possibility. Have we seen test charts from this thing yet?
 
If it's Canon mount I am in. Pl, still a possibility. Have we seen test charts from this thing yet?

It's PL, but people already asked me if Nikon and Canon mounts are an option. I'll forward the question to Nan.

The final offer will be in later this week, latest early next week. Photos and test charts will be online later next week. But it will be (more or less) similar to the standard lens, to which you can find some good previews/reviews online.

Cheers
David
 
What is the degrees of focus rotation after the rehousing?
what will the turnaround time be from point of order to final delivery?
 
What is the degrees of focus rotation after the rehousing?
what will the turnaround time be from point of order to final delivery?

The only info I have is:

1) Sigma 18-35mm F1.8 Lens base;
2) 6063 Alumium Rehoused Lens body;
3) Stainless steel PL mount;
4) 0.8 module gears;
5) New re-designed Lens focus/zoom/ aperture system to get the longer roration compare to the original condition;
6) 95mm front diameter;
7) Weight: 1.5 KG
8) price: 3500 USD
 
Canon mount does make sense if the lens gets cinevised and the degree of rotation for focus change as well. The great thing about a canon mount is being able to use higher end cinema lenses (zeiss CP, canon cinema zooms or Schneider lenses) or very light weight canon DSLR lenses when needed without the need to change the lens mount on the epic/scarlet. Of course a removable canon/PL would be even better! I am in if it's a canon mount lens. Please send me pass for blog.
 
Canon mount is electronic.
It does much more than holding the lens.
Rejecting that is going backwards... just saying...
 
Well - if "cineviziing" some of my other Canon lenses with Duclos makes sense, why doesn't this?
 
I agree to a certain extend...but the electronics are not very useful in its current configuration on the Epic (focus, iris etc...) now your mount on the other hand is different and does indeed make good use of the electronics. ironically you are using the electronics in your mount to make the electronic lenses behave more like manual lenses! :)
 
Well - if "cineviziing" some of my other Canon lenses with Duclos makes sense, why doesn't this?
because you either cinevise an old fully manual lens that has no electronics thus no advantage of electronic mounts, OR you just put a gear on focus and zoom(on AF lens) thus not modifying he internals of the lens so the electronics can still be utilized, OR you getting a full PL conversion thus while the electronics are aborted the lens now is fully compatible with other PL lenses so there is no need to keep changing the mounts and possibly dealing with dirt, back focus issues on location (sometimes remote and dusty..)
 
I agree to a certain extend...but the electronics are not very useful in its current configuration on the Epic (focus, iris etc...) now your mount on the other hand is different and does indeed make good use of the electronics. ironically you are using the electronics in your mount to make the electronic lenses behave more like manual lenses! :)
I'm convinced there is a major advantage in utilizing the electronics rather than aborting them and getting one adapter kit that can be used with 200 lenses as opposed to chopping up 200 lenses.
I may be wrong...:wink5:
And believe me I'm speaking from experience- I've chopped up a lot of lenses- it's not easy and sometimes not pretty...
 
I'm convinced there is a major advantage in utilizing the electronics rather than aborting them and getting one adapter kit that can be used with 200 lenses as opposed to chopping up 200 lenses.
I may be wrong...:wink5:
And believe me I'm speaking from experience- I've chopped up a lot of lenses- it's not easy and sometimes not pretty...

Hey I think what you did with your mount is fantastic....now just get us some more info, pictures, details on mounting options, size, weight etc. I am not questioning your product at all, the reason why more info would be nice is simply to know rigging possibilities and how to best use it and make it work in our style of shooting. I think what you did is def the way to go.
Sorry...not meaning to hijack this thread.
 
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