SLR Zoom vs Prime Lenses on Bolex

danny bartle · December 7, 2004

Hello,

I need reasonably long telephoto lenses for my Bolex RX5. I'm debating whether to use an almost new 35mm SLR Pentax Sigma 70-300mm APO f4-5.6 zoom lens with a c-mount adaptor or using a set of 3 older 35mm SLR Pentax Super Takumar M42 screw mount lenses with c-mount adaptor, a 300mm f4, 200mm f4 & a 90mm f2.8. All these older lenses are optically in great condition.

One person has told me that the newer zoom lenses will possibly be better than older prime lenses as they have newer coatings, technology etc but I always thought prime lenses were optically better?

Thank you...

Chris Keth · December 9, 2004

Hello,

I need reasonably long telephoto lenses for my Bolex RX5. I'm debating whether to use an almost new 35mm SLR Pentax Sigma 70-300mm APO f4-5.6 zoom lens with a c-mount adaptor or using a set of 3 older 35mm SLR Pentax Super Takumar M42 screw mount lenses with c-mount adaptor, a 300mm f4, 200mm f4 & a 90mm f2.8. All these older lenses are optically in great condition.

One person has told me that the newer zoom lenses will possibly be better than older prime lenses as they have newer coatings, technology etc but I always thought prime lenses were optically better?

Thank you...

<{POST_SNAPBACK}>

How old are the primes? They'd probably have to be pretty old to have poor optical coatings. Personally, I'd probably take the primes because of the better speed.

danny bartle · December 10, 2004

hi,

perhaps I should re-phrase my original question...

which 35mm SLR lenses (any brand, Nikon, Pentax, etc) would be best for 16mm using a c-mount adaptor? I need focal range roughly in the 70-300m area. Don't have to be too fast as its all for bright outdoor shooting.... if I could find a good quality zoom in that range or similar or set of 3 primes i'd be happy...

Sam Wells · December 10, 2004

But what kind of work are you doing with it ? If sports, wildlife etc the zoom could have some real advantages.

Actually zooming with SLr lenses can be a PITA, but you've got the range of focal lengths.

I love primes too but w/ a 9.5, 10mm I can just move a foot to reframe.

But at 300mm...... !

I don't reallyknow the lenses in question. A local camera store owner I know seems to be a fan of the Sigma zoom - I watched him try and sell one to a Canon SLR owner over the Canon zoom the guy was considering.

(But the customer bought the Canon as I knew he would, because he was headed to Athens to shoot the Olympics. I told my friend "that guy doesn't want to be seen by his peers with a Sigma lens no matter how sharp it might be" :D

-Sam

Dana Morris · December 14, 2004

Hello,

I need reasonably long telephoto lenses for my Bolex RX5. I'm debating whether to use an almost new 35mm SLR Pentax Sigma 70-300mm APO f4-5.6 zoom lens with a c-mount adaptor or using a set of 3 older 35mm SLR Pentax Super Takumar M42 screw mount lenses with c-mount adaptor, a 300mm f4, 200mm f4 & a 90mm f2.8. All these older lenses are optically in great condition.

One person has told me that the newer zoom lenses will possibly be better than older prime lenses as they have newer coatings, technology etc but I always thought prime lenses were optically better?

Thank you...

<{POST_SNAPBACK}>

Hi,

I shoot surf films with my bolex rex 5 and I have a 150mm YVAR Cmount lens which is about a 300mm lens in 35. You can get them off of ebay for around a couple hundred dollars. I also got a 650mm telephoto Century lens (c-mount) from this great guy at Infraredvideo.com He has a bunch of old cmount telephoto lenses. hope that helps

Dana Morris

Reel Life Films

Sam Wells · December 14, 2004

Had a 150mm macro-Yvar at one time, sold it, regret it. :(

Especially as I picked it up brand new for $ 160 at a store close-out..

(I had to throw it in as part of the deal when I sold a Rex 5)

oh well....

-Sam Wells

ps yes but a 300mm lens is still a 300mm lens

andrewbuchanan · December 14, 2004

My two cents...

I think the lenses will work... but what kind of quality do you desire? If I were going to to shoot with SLR zooms, I would certainly want THE BEST I could get my hands on. Sigmas and Takumors(?) are not in league with say a Nikon ED zoom, nowhere close. If you go with an SLR zoom, I'd look for the newest, and fastest Nikkor, Contax, Leica, Zeiss that I could get.

SLR lenses are also trouble for rack focus - especially when they are mounted in an adapter. Even if you can squeeze someone in beside the camera to rotate the lens, often the adapter isn't machine to exacting standards and the lens can wobble juat a tiny bit - which doesn't look so tiny when projected. Finally be cautious when hanging a bigg-arse zoom off the front of a c-mount. This mount was not made to carry large heavy zooms, so it can flex just enough to cause some focal problems or worse yet rips the threads out of the camera.

Also, I wouldn't think about exposure and lens speed as just an issue of brightness... think about your depth of focus as well. I really like to have a short focus in some of my work and working with a f4.5 zoom, make it a real pain to get. With f1.8 or f1.4 primes I just drop in enough ND and get what I want.

I'm not against SLR zooms and primes and use them from pretty often (expecially my super telephoto nikkor primes). And good lenses can result in a very good image. I just think these things are important to think about before one makes the decision to use them.