Luminous Landscape Forum

Equipment & Techniques => Medium Format / Film / Digital Backs – and Large Sensor Photography => Topic started by: jaisfoto on October 04, 2011, 03:57:31 pm

Title: question on using a Makro lens for silvestri flexicam.
Post by: jaisfoto on October 04, 2011, 03:57:31 pm

Hello again,

i'd like to buy a silvestri flexicam with several digital LF lenses in order to benefit maximum a hasselblad cfv39.
i think it's very a interesting camera (price/quality). but the only thing which makes me worried, it's the limit of focal length.
for about 25 percent of my shooting,  i have to use the makro lenses for between 1:2  and 1:1.
my question is simple. What is maximum rail length (Between chip plain and lens) with the silvestri accessories like extension bayonet?

In silvestri's website, i've seen the 39mm circular lens panel and 30mm extension bayonet ring. if the two stuffs can be used together,the maximum extension would be 90mm(rail)+39mm(lens panel)+30mm(extension ring) = 159mm !!!
Is it right calculation ???

I've sent question email to silvestri but no response.

Title: Re: question on using a Makro lens for silvestri flexicam.
Post by: TH_Alpa on October 04, 2011, 04:29:43 pm

Jais,

I don't know about the mechanical maximum possible extension of the Silvestri cam, but depending on the macro lens focal length you have to know that at a scale of 1:1 the distance lens to image/focus plane will be 2 x the focal length. For example, if using a 120 Macro, your distance lens to image plane needs to be 240 mm. At 1:2 it is 1,5 x focal length = 180 mm.

Thierry

Quote from: jaisfoto on October 04, 2011, 03:57:31 pm

for about 25 percent of my shooting,  i have to use the makro lenses for between 1:2  and 1:1.
my question is simple. What is maximum rail length (Between chip plain and lens) with the silvestri accessories like extension bayonet?

Title: Re: question on using a Makro lens for silvestri flexicam.
Post by: jaisfoto on October 04, 2011, 07:59:49 pm

Thierry,

Thanks for your reply. of coarse i know about focal length calculation according to ratio.
i just don't know if Sivestri extension bayonet ring and lens panel work together.
As i know, there're usually 2 different macro lenses (80mm or 120mm for digital LF lenses)
if i use 80mm lens, i'll need 160mm distance between chip plain and lens' center point.
i wanted to know if i could have 160mm with these accessories
 

Title: Re: question on using a Makro lens for silvestri flexicam.
Post by: tom_l on October 05, 2011, 01:33:18 am

Hi,
i no longer have my flexicam, i switched it for the Bicam.
But, i remember something about not using longer lenses than 105mm (LF lenses) on the Flexicam. Is this because of the limited extension or the weight of the lens.? My longest LF lens was the 100mm S-K, the longest Hasselblad lens I used was the 120 CFI.

Tom-

Title: Re: question on using a Makro lens for silvestri flexicam.
Post by: jaisfoto on October 05, 2011, 02:02:44 pm

Tom,

when you used 100mm lens, did you mounte it on what kind of panel?
Do you know about the extension ring?

thanks for your attention

Title: Re: question on using a Makro lens for silvestri flexicam.
Post by: tom_l on October 05, 2011, 02:54:59 pm

Hi Jais,

here a list of the Felxicam lenses
http://www.silvestricamera.it/tabelle_pop_up/tabella_bayonets.htm
the bayonet for my 100mm is C0090
The rodenstock 105mm is the longest lens on the list

here a general page with some info about extension rings :
http://www.silvestricamera.it/eng/prodotti_eng/Flexicam/Flexicamlens.htm

 retry contacting (Silvia) Silvestri, she should be able to help you with your questions.

Tom

Title: Re: question on using a Makro lens for silvestri flexicam.
Post by: BillOConnor on October 05, 2011, 09:05:59 pm

The American rep for Sylvestri is Ted Bromwell. He is knowledgeable and very helpful. www.bromwellmarketing.com

The other tact is to use the Hasselblad adapter and extension tubes, if needed. Each lens has its own focusing mount.
I think with the back extensions, the front extensions and the focusing mount, you should be able to focus close enough.