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rutwij
21st December 2012, 08:47 AM
I recently bought a Bigma from a forum member (already left him positive feedback in the feedback thread).
Now I was wondering if the lens is weather sealed. Would I wreck it if I took it out on a typical Scottish day? Would I need to hide it away at the first sign of moisture?

Rutwij

theMusicMan
21st December 2012, 08:52 AM
I don't believe the Bigma is weather sealed so I'd take care with it. Maybe use a lens cover if it is raining or wet.

Slight or light drizzle shouldn't be a problem as long as you have a cloth to dry it regularly.

Chevvyf1
21st December 2012, 09:15 AM
As a past owner I only took her out on bright & sunny DRY days
best hope Duncan (new owner) sees thius and replies about "typical Scottish days" :)

Tordan58
21st December 2012, 09:31 AM
No, the Bigma is not weather sealed. And it's prone to collect dust as well.

rutwij
21st December 2012, 11:25 AM
Thanks everyone. I'll take extra special care of the lens :)

rutwij
2nd January 2013, 01:52 PM
I just noticed that the lens creeps up or down under it's own weight when inclined or upright. Is this the way the lens is designed? Or is it a fault in the lens?

Chevvyf1
2nd January 2013, 01:54 PM
BIGMA has a "Lens lock" to stop this :)

Jim Ford
2nd January 2013, 01:55 PM
I just noticed that the lens creeps up or down under it's own weight when inclined or upright. Is this the way the lens is designed? Or is it a fault in the lens?

I haven't got one, but I believe that this is not uncommon. My Zuiko 50-200mm does it.

Jim

David M
2nd January 2013, 02:10 PM
Jim, I don't remember my copy of the original 50-200 creeping and my SWD version doesn't creep. Non of my HG and SHG lenses creep, I've always assumed the O rings used for the sealing caused enough resistance to stop zoom creep. Maybe your O rings are getting worn.

Tordan58
2nd January 2013, 02:14 PM
My Bigma is creeping when pointed down. I believe it is "by design". There is a mechanical lock to prevent it.

None of my Zuiko zooms do (70-300, 50-200).

/Tord

rutwij
2nd January 2013, 02:43 PM
The lens lock feature only seems to work when the lens is fully retracted. When engaged past 70mm or so, it does nothing to prevent further movement except down to 50mm. Perhaps it's the lens lock which is broken?

PeterBirder
2nd January 2013, 03:04 PM
Don't worry there is nothing wrong with your lens.

The Lens Lock is only intended to lock it in the retracted position. There is so much heavy glass in this lens that if the zoom mechanism was made stiff enough to stop it creeping it would be too stiff for you to turn it.:)

I had one of these lenses for several years and it behaved just as yours does.
I also got it a bit wet in the rain a few times but suffered no ill effects. Just take sensible precautions and if you should get caught in the rain wipe the outside dry with a cloth as soon as possible before you retract it.

Most of all enjoy using the lens, it's a cracker.

Regards.*chr

Benedict
2nd January 2013, 03:49 PM
I just noticed that the lens creeps up or down under it's own weight when inclined or upright. Is this the way the lens is designed? Or is it a fault in the lens?

It does suffer from lens creep due to its weight,as Chevvyf1 says there is a lock on the lens barrel,although I have seen a rubber band type contraption advertised on Ebay for a few pounds and which further helps prevent this.

HTH

Jim Ford
2nd January 2013, 04:50 PM
Jim, I don't remember my copy of the original 50-200 creeping and my SWD version doesn't creep. Non of my HG and SHG lenses creep, I've always assumed the O rings used for the sealing caused enough resistance to stop zoom creep. Maybe your O rings are getting worn.

'Lip seals' are used, rather than 'O' rings for sealing (they're different).

To prevent wear and friction (a reported problem on the 50-200mm, which can eventually destroy the seal and jam the lens) I occasionally lubricate the lens barrel with dry silicone lubricant. This also repels water at the vulnerable barrel/seal interface, which prevents water from being 'dragged' into the lens interior. It also means if I carry the camera with the lens hanging down, it will eventually extend fully because of the reduced friction.

I've mentioned before, that silicone lubricant has a characteristic silky 'feel'. When I've bought new lenses, they have had the same feel, but eventually lose it in use. This leads me to suspect that silicone lubricant is used in their manufacture.

Both my SHG lenses (7-14 and 35-100) zoom internally, so the above doesn't apply.

Jim

David M
2nd January 2013, 05:26 PM
I thought the 7-14 was internal zoom for a few years after I got it until someone on a forum pointed out it was external. When you zoom the 7-14 the front group moves in and out inside the built in lens hood by a few mm.

peak4
2nd January 2013, 06:03 PM
The Lens Lock is only intended to lock it in the retracted position.

I also got it a bit wet in the rain a few times but suffered no ill effects. Just take sensible precautions and if you should get caught in the rain wipe the outside dry with a cloth as soon as possible before you retract it.

Regards.*chr

I would also try and keep it dry and dust free if you plan to fully extend it from closed. The "trombone" effect can also be likened a bit to a syringe. As you extend the lens, it draws air in along with any spurious dust and moisture.

Also re the lens lock.
I would concur that it is purely to hold the package to its shortest length for transport, but would suggest another gentle warning.
It seems to hold the lens shut by a plastic tab along the lines of a small door bolt.
If you engage the lock, either on purpose or by accident when the lens is extended, it won't have any effect. However, if you then retract it too quickly I think you could bang the front tube onto the locking tab internally and potentially cause some damage.
I think you'd probably have to do it quite forcefully, but I have read of a couple of folks who have had the locking tab break off internally, leaving an errant bit of plastic to be extracted back at Sigma's repair centre.

None of this is anything to worry about or to spoil your enjoyment of what is a fine lens capable of very good results, at an almost affordable price.
It's a great shame that it's now discontinued; I just hope the spares stacks are adequate to keep the lenses in service for a few years yet.

Enjoy it.

Jim Ford
2nd January 2013, 07:05 PM
I thought the 7-14 was internal zoom for a few years after I got it until someone on a forum pointed out it was external. When you zoom the 7-14 the front group moves in and out inside the built in lens hood by a few mm.

Ahh - I hadn't noticed!

Jim

Imageryone
2nd January 2013, 11:00 PM
If damp could be a problem in your lovely weather, a large Ziplock bag with plenty of silica gel bags in it is the answer. Wipe the lens down well, then put it in the bag and leave to dry thoroughly as you travel home. Then store it in a warmish place when you get back.
30 secs in a microwave drys the silica gel ready for next time.

Silica Gel bags of various sizes from www.jackthehat.co.uk