Forgot Password
Pentax Camera Forums Home
 

Reply
Show Printable Version Search this Thread
03-10-2009, 05:26 AM   #1
Site Supporter
germar's Avatar

Join Date: Apr 2007
Location: Austin Texas
Photos: Gallery
Posts: 728
How much weight can that M42 adapter take?

Folks:

I have happily used a wide range of screwmount lenses on my K10D with no issues. I've just taken ownership of a beautiful Takumar 300/4 that weighs about 1350 grams, the biggest and heaviest lens I've ever owned. I will be attaching it to a K10D with a battery pack, so the whole thing is suitable for a weightlifting working out.

The lens has a tripod mount, so I can balance the entire rig, but I have my doubts about stressing the Pentax M42 adapter with SO MUCH weight. Any advice, and experiences with really heavy lenses? I am using a genuine Pentax adapter, but I also have the "Bower" brand from B&H which is heavier metal but requires a tool for removal.

Any feedback about heavy weight hanging off this little adapter ring?

much thanks,

germar

03-10-2009, 05:34 AM   #2
Veteran Member




Join Date: Mar 2008
Location: Nowhere, Sweden
Photos: Gallery
Posts: 654
I have been running around the forests with the lens mounted to the camera in a R-Strap attached to the camera. Without noticing any problems. The tripodmount weight alot by itself, so remove it if your going to do it for a long time i guess.

I have probably had it mounted and running around for 30 hours or so total without any problems at all. Ofcourse, if you have a strap that can be mounted on the tripod mount (such as the R-Strap), you should. But I do not think that you have to worry too much.
03-10-2009, 05:38 AM   #3
Veteran Member
Jimfear's Avatar

Join Date: Apr 2007
Location: Uppsala, Sweden
Photos: Gallery
Posts: 576
I don't think there is any big risks in this. The adapter sits tight on the lens so it's basically the same as a K-mount lens. And the mount can probably hold a lot of weight. I have not had any problems with my 450mm lens that also puts a lot of strain on the mount and adapter.

I wonder what brakes first though, does the metal on the lens bend or break or does the whole mount come of the camera? Any thoughts on this?
03-10-2009, 05:45 AM   #4
Veteran Member




Join Date: Mar 2008
Location: Nowhere, Sweden
Photos: Gallery
Posts: 654
QuoteOriginally posted by Jimfear Quote
I wonder what brakes first though, does the metal on the lens bend or break or does the whole mount come of the camera? Any thoughts on this?
I doubt anything will bend, possibly that the mount on the lens (in this case the adapter) will get grinded down so that it does not fit anymore. The mount on the camera is very firmly stuck in the entire chassis inside the camera which is steel and will not break for such small weights. You could probably mount a hook in it and hang in it with your bodyweight.

I also doubt that the m42 thread will break for such little weight. So the weak link would be the flanges on the adapter. Which on the genuine (cant speak for others) seem strong enough to hold for quite a weight. Only if the edges on it was grinded down thru wear, I think it would be a risk for the lens. But hopefully, if that happens you will notice it far in advance.

So, just check the adapter and m42 threads now and then and I am sure youll be fine. And the old takumars are tanks, if you manage by force to bend the barrel of a Takumar, I will be impressed of your muscle mass.

03-10-2009, 06:32 AM   #5
Pentaxian
Wheatfield's Avatar

Join Date: Apr 2008
Location: The wheatfields of Canada
Posts: 10,155
If you put too much weight on the mount you can warp the chassis of the camera. I wouldn't be supporting a 3 pound lens by the camera body myself, but then, that's just me.
03-10-2009, 07:25 AM   #6
Site Supporter
stevebrot's Avatar

Join Date: Mar 2007
Location: Vancouver (USA)
Photos: Gallery | Albums
Posts: 27,415
I think the capacity may vary depending on the brand of adapter. Some of them have rather small "ears" for engaging the body. Materials also vary. Some are chromed brass, some are aluminum, and others are stainless steel.

Steve
03-10-2009, 07:27 AM   #7
Veteran Member
Gooshin's Avatar

Join Date: Sep 2007
Location: Toronto, the one in Canada.
Posts: 5,611
QuoteOriginally posted by germar Quote
Folks:

I have happily used a wide range of screwmount lenses on my K10D with no issues. I've just taken ownership of a beautiful Takumar 300/4 that weighs about 1350 grams, the biggest and heaviest lens I've ever owned. I will be attaching it to a K10D with a battery pack, so the whole thing is suitable for a weightlifting working out.

The lens has a tripod mount, so I can balance the entire rig, but I have my doubts about stressing the Pentax M42 adapter with SO MUCH weight. Any advice, and experiences with really heavy lenses? I am using a genuine Pentax adapter, but I also have the "Bower" brand from B&H which is heavier metal but requires a tool for removal.

Any feedback about heavy weight hanging off this little adapter ring?

much thanks,

germar
This is why you should utilize your lens's tripod mount! That way the camera is only supporting itself.

If you are machine gunning it, simply hold the barrel with your other hand (although i cant imagine you holding this thing otherwise)

so really dont worry, just dont lift by the body and you'll be fine.
03-10-2009, 07:48 AM   #8
Inactive Account




Join Date: Dec 2008
Location: Ames, Iowa, USA
Photos: Albums
Posts: 2,965
I think the first thing to fail might be the screws holding the mount receiver plate to the camera. That'd take a LOT of force.
Dave

Reply

Bookmarks
  • Submit Thread to Facebook Facebook
  • Submit Thread to Twitter Twitter
  • Submit Thread to Digg Digg
Tags - Make this thread easier to find by adding keywords to it!
adapter, k-mount, k10d, lens, lenses, m42, m42 adapter, pentax, pentax lens, slr lens, weight
Thread Tools Search this Thread
Search this Thread:

Advanced Search


Similar Threads
Thread Thread Starter Forum Replies Last Post
Who wants to lose some weight (a weight loss challenge!) jct us101 General Talk 290 05-03-2013 11:49 AM
For Sale - Sold: Industar 50-2 50mm f/3.5 Soviet M42 lens + M42 Adapter 65535 Sold Items 10 11-27-2009 04:18 PM
For Sale - Sold: M42 Tair 11-A (135mm, F2.8), Genuine Pentax M42 to K adapter PrimeObjectif Sold Items 15 11-02-2009 07:20 PM
For Sale - Sold: Volna-9 M42: 50mm/f2.8 1:2 macro.+ M42 adapter + auto ext.tube. pcarfan Sold Items 6 05-16-2009 02:53 PM
For Sale - Sold: PK/M42 adapter and M42 Macro extension tubes mayoapo Sold Items 1 08-26-2007 05:19 PM



All times are GMT -7. The time now is 11:59 AM. | See also: NikonForums.com, CanonForums.com part of our network of photo forums!
  • Red (Default)
  • Green
  • Gray
  • Dark
  • Dark Yellow
  • Dark Blue
  • Old Red
  • Old Green
  • Old Gray
  • Dial-Up Style
Hello! It's great to see you back on the forum! Have you considered joining the community?
register
Creating a FREE ACCOUNT takes under a minute, removes ads, and lets you post! [Dismiss]
Top