Tamron 90mm 1:1 with raynox

[Mmmm]

I really wanted to pair my tamron with some sort of close focus diopter and finally settled for a raynox closeup lens. They come in two flavours, the 150 and the 250 and I needed some information about what effect they would have with my tamron lens so that I could decide which to buy.
However I couldn't find this information anywhere so I crossed my fingers and blindly went ahead and bought the 150. So for anyone else with the same questions, here are my findings regarding magnifications and focus distance.

My sensor is 23.6mm wide

Infinity focus with 150 attached

This was 200mm from the very end of the Raynox. (lens probably recessed about 8mm) to give 23.6/56=0.42x magnification (about 1:2.4)

Closest focus with 150 attached

This was 55mm from the end of the Raynox - gives 23.6/16=1.48x magnification (about 1.5:1)

So the working distance range is 55mm - 200mm
with magnifications of 1.5:1 - 1:2.4


So what about a comparison of working distances at the same magification?
Closest focus of Tamron 90mm without 150

This was 94mm from the end of the lens - gives magnification of 23.6/23=1.03x (1.03:1)

Setting up the lens with the raynox attached so that the exact same area is in the frame: This turned out to be where the lens markings read exactly 1.1ft
lens set to 1.1ft with 150 attached

The distance from the end of the Raynox to the subject was 80mm at this magnification
So you lose about 94mm - 80mm = 1.4cm of working space when you attach the raynox at this magnification.

Looking at the first image, the max working distance with the raynox attached is 200mm which fits in 56mm of ruler
Tamron 90mm at 56mm width without 150 attached

The working distance here was 225mm

so 225mm - 200mm = 2.5cm lost working distance.

 

[Mmmm]

and some pictures comparing the lens at closest focus with and without the 150 - so you can really see the difference.
With

:

Without

In Summary:

The working distance range is 55mm - 200mm with magnifications of 1.5x - 0.42x (1.5:1 - 1:2.4)

At 1:1 magnification the 150 requires you to be 1.5 cm closer to the subject than you have to be without the 150.
At the other end (0.42x magnification) you need to be 2.5cm closer.

Conclusion:

First of all, the quality is great and there is no sign of vignetting at any magnification with this lens.

The increase in magnification is not really that much with the Tamron 90mm - from 1x to 1.5x - with a hit of 1.5cm working distance at the 1x end. From my pencil shots I realize that I really want to get closer than this...

So I'll be sending it back and getting a 250..(it's only £5 more at the moment). Hopefully the working distance won't be too extreme...

 

[Mmmm]

For some "in the field" pictures see this thread: In the Field

 

[Mmmm]

I sent the 150 back and am now the proud owner of the 250!

I've done some tests with my tamron 90mm and here are the results along with those of the DCR-150.

Infinity focus:
DCR-150
Working distance 200mm
Width 56mm (0.42x or 1:2.4)

DCR-250
Working distance 120mm
Width 33mm (0.72x or 1:1.4)

Closest focus:
DCR-150
Working distance 55mm
Width 16mm (1.48x or 1.5:1)

DCR-250
Working distance 45mm
Width 13mm (1.82x or 1.8:1)

16mm width (1.48x closest with DCR-150)
DRC-150 working distance 55mm

DRC-250 working distance 57mm

1:1 focus
No diopter
Working distance of 94mm (0.96ft on focus dial - closest focus)

DCR-150
Working distance of 80mm (1.1ft on focus dial)

DCR-250
Working distance of 83mm (1.5ft on focus dial)


Here are three pencil shots at closest focus:
Pencil at closest focus without any diopter

Pencil at closest focus with DCR-150

Pencil at closest focus with DCR-250

Incredible results - The DCR-250 actually has better working distances than the DCR-150 for 1:1 or greater magnification!!!!!

I'm really glad I sent the 150 back

A really handy thing I've just noticed is that turning the focus limiter on on the lens with the DCR-250 attached ensures that all shots will be over 1:1...very nice - so I'll know that if I need to get further away I should remove the raynox....