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Sigma Lens Service

Steve Oakley
 

Has anyone had a lens winterized by Sigma ? I'm under warranty right now. Specifically my problem is I bought the 50-100 1.8 EF regular stills lens a few months ago. I bought the stills vers because it has autofocus available, the cine vers doesn't.  When using it in the cold 20 deg F I found the zoom ring became very stiff. I sent the lens into Sigma ( NY / LI ) last week to have the zoom ring tension loosened up and regreased with a lube suitable for cold temps. Lens came back basically identical. I put it in the freezer for 2 hrs at 0 deg F and the lens zoom ring basically wouldn't turn. As the lens warmed up, function returned. 

I find it hard to believe that a product being sold as a Pro lens would have such serious cold weather problems. I currently am awaiting a call back from Sigma service so the manager can talk to the tech that worked on the lens and see what they say. Is this normal for them ? is cold temps a problem for their glass ? I know canon and others ( including local lens shop that does cine mods to still lenses ) offer service to regrease lenses for cold ( or extreme heat ) so I'd expect this is no big deal for Sigma... or is it ? anyone with any experience ?

I met some one at the Sigma booth at NAB a couple weeks ago and he said no problem to get it taken care off.

Also FWIW, while the focus ring got a bit stiffer, it still worked reasonably ok.

Steve Oakley

DP / Editor / Colorist / VFX Artist

Madison & Milwaukee WI

920 544 2230

 

Matthew Duclos
 

A couple of items here... If the zoom ring didn't loosen up when you brought it back to warmer climate, then I suspect there's something else wrong with your lens. While Sigma's still photo lenses are indeed weather resistant, no lens is going to operate the same in freezing temperatures as it does in warm weather unless it's been particularly prepared for such conditions. I've done this on many occasions for arctic projects as well as NASA related projects that required extreme measures. I'd be curious to know what measures the shop you're familiar with takes to prepare a lens for extreme heat. And lastly, we see many, many complaints of zoom "stiffness" which can be very difficult to assess without actually holding the lens or placing it on a torque meter to gauge accurate resistance. What one person considers "tight" may be perfectly acceptable to another operator. At the end of the day, if you're not happy with the lens, I would request a complete swap from Sigma or at the very least from the dealer who sold you the lens. 

P.S. If you're putting your lens in a freezer and taking it out to test, I highly recommend observing safe procedures for temperature fluctuation or you could be doing even more harm (condensation, temp shock, etc.)  
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- Matthew Duclos
Lens Tech/Geek

Steve Oakley
 

Hi Matt

On Apr 30, 2018, at 5:08 PM, Matthew Duclos <Matthew@...> wrote:

A couple of items here... If the zoom ring didn't loosen up when you brought it back to warmer climate, then I suspect there's something else wrong with your lens.
lens returned to “normal” when warmed up. grease problem, or really tight parts / contraction problem.

While Sigma's still photo lenses are indeed weather resistant, no lens is going to operate the same in freezing temperatures as it does in warm weather unless it's been particularly prepared for such conditions.
freezing temps is subjective. I’d expect reasonable operation down to 0 F or maybe 10F before needing to consider changing out lens grease. some days though, its a balmy -30F which is a whole other situation to be working in.

. And lastly, we see many, many complaints of zoom "stiffness" which can be very difficult to assess without actually holding the lens or placing it on a torque meter to gauge accurate resistance. What one person considers "tight" may be perfectly acceptable to another operator. At the end of the day, if you're not happy with the lens, I would request a complete swap from Sigma or at the very least from the dealer who sold you the lens.
I get it that people prefer different levels of resistance in their lenses. that said, its pretty stiff and less than pleasant to use. easily 2X stiffer than focus ring which seems fine. yes it would be nice if there was an easy simple way to state turn resistance so we could all be talking about the same thing rather than subject terms / amounts.

I was looking to collect more information first before having to deal with a swap out. I already had the lens gone for 2 weeks with shipping.

P.S. If you're putting your lens in a freezer and taking it out to test, I highly recommend observing safe procedures for temperature fluctuation or you could be doing even more harm (condensation, temp shock, etc.)
yes of course I had it in a tight fitting plastic bag to prevent condensation

Steve Oakley
DP / Editor / Colorist / VFX Artist
Madison & Milwaukee WI
920 544 2230

Steve Oakley
 

update : Sigma is taking the lens back again. they had to check with factory in Japan on lens specs. short vers is lens should be good down to about -27F… which is good because I’ve been in those temps. so I’ll give it a week and see how it goes.

My *guess* : factory got a barrel of lens grease that has the wrong stuff in the right container or something along those lines.

Steve Oakley
DP / Editor / Colorist / VFX Artist
Madison & Milwaukee WI
920 544 2230

Steve Oakley
 

UPDATE 2

lens went back to Sigma for 2nd go around. this time they gave my lens and a couple samples a deep freeze. all acted the same - the zoom ring got super stiff at 0F while the focus was ok. It appears that their spec is to be operational down to -10C or 14F, big difference from what I’d thought they had said was -20F on a previous call. Even at 20F the zoom ring is very stiff.

either way, they removed the grease from my lens which may of improved it. They don’t have a special cold temp prep like other manufactures or the better lens service people. I told them send it back, but so far haven’t gotten any shipping info so maybe they decided to mess with it a bit since I’ve heard nothing.

I guess at this point the problem I assume is that when the lens get s cold, the mix of plastic and metal parts has enough contraction to cause clearances to get really tight and the ring gets stiff. the trade off of course may mean at warmer temps things would be a bit too loose. no idea what to expect back, if they are gonna try something else to make this lens workable in cold temps or not.

now this has me wondering - has anyone tried the cine series in cold temps ? or their other zooms in the cold ?

Steve Oakley
DP / Editor / Colorist / VFX Artist
Madison & Milwaukee WI
920 544 2230


On May 4, 2018, at 2:57 AM, Steve Oakley <steveo@...> wrote:

update : Sigma is taking the lens back again. they had to check with factory in Japan on lens specs. short vers is lens should be good down to about -27F… which is good because I’ve been in those temps. so I’ll give it a week and see how it goes.

My *guess* : factory got a barrel of lens grease that has the wrong stuff in the right container or something along those lines.