Rapid View Portrait (RVP) Pictorial lens

[cowanw]

Looking at the two catalogue tables for the TT & H RV and RVP series, I notice that all data is identical - apart from the coverage given (for portrait?) and the lens hood diameter. The range of focal lengths is the same, the specific focal lengths are the same, flange dimensions and the price. So perhaps the RVP is just a large front stop version of the RV (usually called a Rapid Landscape (f11) by other makers)?

Just to make the point that the variation is plate size as compared to same focal lengths is likely just the fact that the length of the brass tube in front of the lens, with the shutter mechanism, acts as a physical obstruction to plate coverage with the RVP at F/8 or so (or wide open).
I had a brass tube made for an 8 inch RV, the length and diameter of the original, but without a stop mechanism, so wide open. The 8 inch RV is designed for a bit larger than 4x5. Wide open, with a lens hood of the same measurements, 4x5 was vignetted by about 1/3 stop. hence the 8 inch RVP was listed for 4 1/4 x 3 1/4, for reasons of physical vignetting.

[peter brooks]

My assumption, (based on just deductive reasoning and no research or surveys), is that TTH put the exact focal length to the 100ths for each individual lens. They acknowledged slight FL variances in this way, and that might have helped the photographers somehow. I seem to remember seeing lots of variation in the numbers after the decimal.

Clarence White stated that the lens he used was a RVP F/11. I think the actual lens might be at Princeton University. I always assumed that he misspoke himself but perhaps there were such lenses, despite the catalogues.

Interesting. Would there be any mileage in starting a list (like the Cooke Portrait lens one)? I'd be happy to look after a spreadsheet and if all the engraving was recorded we could get a better picture of the history - and whether individual focal lengths were engraved.

[cowanw]

Mine RV is No. 11290, Eq Focus 8.8 in, TaylorTaylor&Hobson, Leinster & London, 6 1/2x4 3/4.

[Steven Tribe]

All plain Taylor and all early T,T&H have 2 decimal inch points for all lens types.
My casket set has WAR at 4.12, RR at 7.28 and RV at 8.72 inches.
I have seen at least variation in the engraved second decimal point in "identical" TTH lens. Makes matching of lenses for stereo pairs sensible!

[CCHarrison]

3 Taylors I just picked up... RV 8.1 in. RVP 7.75 in RVP 11.78 in

[peter brooks]

I'm still curious...

Bumping up this old thread because I picked up a whole plate camera with an RVP lens which doesn't match the 1904 catalog page.
It says
8 1/2 x 6 1/2 RVP
EQ. FOC. 12.47 IN
on the barrel and the serial number is 2238.
The aperture diaphragm is clearly the RV lens style and has the max opening of f/11.3....

This lens has 11.3 on the aperture ring, I have seen an advert that lists the RV as 11.3 but have seen photos of other RVs with the ring marked just 11. I wonder at what point did the marking change?

The decimal points on the focal length - given TTH's obviously excellent engineering skills what causes the difference in focal lengths? I can't think that it is vagaries in grinding, is it due to the differing properties of individual pieces of glass? (If so, this kind of variation in focal length must occur in many other early lenses?)

The variation can be quite large - my RVP has Eq Focus of 12.82in, the RVP Dan has just sold is 11.78in. Both are the 8x5 size.

[goamules]

My R.V.P above is an 8x5, serial no. 2818 - Eq Foc 10.75 Inch.

[lucaas]

My R.V.P above is an 8x5, serial no. 2818 - Eq Foc 10.75 Inch.

The focus length and coverage of this RVP accord with mine. 10.75” for 5x8 and 12.47 for 6.5x8.5. And the serial numbers are not far away. Maybe TTH changed specifications for later RVPs?

[peter brooks]

That's an even greater variation - 10.75in to 12.82in for 5x8 coverage. As Lucaas suggests, maybe a design or specification change through the years?

The aperture spec of 11.3 was puzzling, then I realised (while lying in bed, of course, mind rambling about) - 11.3 is twice 5.6 (or thereabouts), so is absolutely correct. (therefore f22 should be f22.6 or something like that ).

Looks like Garrett's RVP (above) still has 11.3 marked on the aperture ring (although it goes to f8).

[CCHarrison]

For research purposes...