Venus Lens at 2:1

[Bilbo_baggin]

The Venus Lens:


Below are 3 images where the Venus is set to it's maximum magnification (twice life size, or 2:1) and each of these were processed in Lightroom using only that programme's "Auto" process button which set the sliders to where it thinks they should be. This doesn't alter the clarity slider, which I use during my normal editing. Other than that, they are just resized and sharpened for the web using an action by Steve Perry.


All 3 were at around f/11, 1/250sec, ISO 100, ringflash on the front of the lens. Working distance from end of lens was about 2 inches I suppose.




The first is a One Pound coin, the second is a car indicator lamp showing the filament, which I measured as being four millimetres across, and the third is the Queen's eye on a Ten Pound note (be aware, I couldn't get the money totally straight at the edge as I had it in clothe pegs to try and keep it upright, but it wasn't quite level with the focal plane across the whole view, and at this magnification, even a millimetre out would mean a loss of focus/sharpness.















Paul.

[elephantsoup]

Wow just wow I wants

Also could you recommend a cheap ring flash that works

[Bilbo_baggin]

Wow just wow I wants

Also could you recommend a cheap ring flash that works

I use a Marumi ringflash which is cheap but cannot be controlled except by reduce the EV in the camera. You can buy LED ones, which are meant to do good jobs too though.

One big problem is illuminate the subject enough when its dark (a lot of insects come out at night only) as you have to get very close and of course the camera and lens then takes away a lot of light by getting in the way of it!


Paul.

[Teajunkie]

They are fantastic paul.

i know what to add to my Xmas list
on a side note I have an led ring flash and that can be switched to illuminate on constant light with varying brightness.
happy to lend it to you if you want to try it?

[Bilbo_baggin]

They are fantastic paul.

i know what to add to my Xmas list
on a side note I have an led ring flash and that can be switched to illuminate on constant light with varying brightness.
happy to lend it to you if you want to try it?

Generous offer mate, thanks, but Devon to Lancashire is a long way...

I'm looking to make some diffuser of some kind, but if you can link me to where you bought yours I can check it out for future reference.

Cheers buddy.

Paul.

[elephantsoup]

Just saw this on amazon...
http://www.amazon.co.uk/s/ref=nb_sb_...Flash%20RF550D
cheap if nothing else

[Bilbo_baggin]

Interesting. I'll check ebay.


Paul.

[elephantsoup]

Interesting. I'll check ebay.


Paul.

I am ordering based on this guys review on amazon...

I'm quite impressed with this 'Travor' RF-550D (made by Celltech Electronic Company Ltd) Macro Ring Flash. Build quality is good for the price, the only issue will be the plastic lens adaptors, I expect the threads on them to wear out fast if the unit is removed and put back on frequently, so don't expect the adaptors to last years with constant use. I recommend that you are gentle and take your time when fitting the lens adaptor, rush it or be a bit rough and you will strip the plastic threads, I also recommend that you do not over-tighten them, not even finger tight. Leave the adaptor slightly loose for safety.

The amount of light the ring flash/light gives off is quite impressive by illuminating the subject to be photographed extremely well.

(Now for the technical, extremely boring bit that those seriously into photography will probably be interested in and will probably be able to make sense of) Using a digital multimeter with a built in 'Lux light meter' I measured the approximate illumination intensity of a subject (the multimeter itself) at three distances using just three settings of the units 'stepped' variable brightness control (with the light constantly on).

As a comparison on how much this unit will light the subject to be photographed I checked the illumination on the same subject with 2 bulbs, one an incandescent 40w SES spotlight and a 12w ES CFL energy saver. (please don't ask for the figures in Lumen's, that would be really pointless, instead please just google it.)

Cheap 40w SES spotlight bulb:
11,900 lux at 10 cm
1,700 lux at 30 cm
450 lux at 60 cm

12w ES General Electric, Compact Fluorescent:
2,900 lux at 10 cm
1,100 lux at 30 cm
350 lux at 60 cm

The RF-550D for illumination comparison:
At a distance to subject from light of 10cm:
+1.5 setting on brightness control with no diffuser I got 11,800 Lux. (very close to the 40watt bulb illumination level)
0.0 setting on brightness control with no diffuser I got 9,100 Lux.
-1.5 setting on brightness control with no diffuser I got 6,250 Lux.

At a distance to subject from light of 30cm:
+1.5 setting on brightness control with no diffuser I got 2,750 Lux.
0.0 setting on brightness control with no diffuser I got 2,100 Lux.
-1.5 setting on brightness control with no diffuser I got 1,450 Lux.

At a distance to subject from light of 60cm:
+1.5 setting on brightness control with no diffuser I got 740 Lux.
0.0 setting on brightness control with no diffuser I got 570 Lux.
-1.5 setting on brightness control with no diffuser I got 410 Lux.

With the 'Opal white diffuser' attached repeating the above tests:

At a distance to subject from light of 10cm:
+1.5 setting on brightness control with opal diffuser I got 3,550 Lux.
0.0 setting on brightness control with opal diffuser I got 2,780 Lux .
-1.5 setting on brightness control with opal diffuser I got 1,920 Lux.

At a distance to subject from light of 30cm:
+1.5 setting on brightness control with opal diffuser I got 730 Lux.
0.0 setting on brightness control with opal diffuser I got 560 Lux.
-1.5 setting on brightness control with opal diffuser I got 400 Lux.

At a distance to subject from light of 60cm:
+1.5 setting on brightness control with opal diffuser I got 220 Lux.
0.0 setting on brightness control with opal diffuser I got 180 Lux.
-1.5 setting on brightness control with opal diffuser I got 140 Lux.

(Lux light meter accuracy: +/-5%, manufacturer calibrated to incandescent light source at a colour temp of 2856kelvin.)

The LED flash function on the RF-550D emits it's light in approximately 1/100th of a second, it's not as fast or as intense as a strobe flash, you might notice a very slight delay after the shutter release is pressed if you are used to using strobe based flashes.

According to the manufacturer the colour temperature of the light this ring light/flash gives off is 3000kelvin to 15000kelvin, I have no way of testing this claim as the equipment required is well out of my price range (unless I was lucky enough to win the lottery, then I would have a go at it).

This ring flash/light also works on a Fuji Finepix S9000/S9500 bridge camera, the only issue is that with the opal white diffuser attached it will cause chronic light reflections in the lens due to the way the diffuser very slightly catches the edge of the field of view of the lens, this results in optical effects through the lens caused by the light itself, this makes that diffuser useless, I'll guess that the coloured diffusers also cause this issue too on that camera.

The only way I think I can get round that optical interference issue is to mask off the edge of the diffuser closest to the lens with matt black tape. I do not know if this issue exists with other lenses as the lens it was tried on is a 58mm diameter permanently attached 28mm to 300mm manual zoom lens and is non removable. Apart from that minor optical reflection issue, it works perfectly.

The Voltage on the RF-550D at the hot-shoe terminals is just slightly over 3 volts, this is important for some DSLR cameras as many of them cannot handle anything higher than 5v without causing expensive damage to their camera.

For a budget macro ring light I'd give it 8/10 only due to the fact the threads on the adaptors are plastic and will wear out fast with constant use, otherwise it's a nice bit of kit and does what the maker says it will even though it can be a bit too bright for macro use and has a little issue using the lens mentioned above (I'll soon rectify that using a little ingenuity and inventiveness). ;-)

Update:
A thin strip (5 mm wide) of black tape stuck to the inside edge of the diffusers sorted the lens from being overwhelmed and blinded by light being visible to the lens on the inside edge of them when fitted on the camera I mentioned in the review. No more problems through that lens now, it's perfect. ;-)

EDIT.. ah damn all hong kong based shipping. ebay for me too

[Teajunkie]

That's the ring flah I have
bought it on eBay about 2 years back cost a bit more than that thought at the time.

Great bit of kit although it doesn't produce that much light.
If you pay postage paul I don't mind shipping it although buying one new would probably work out less

[Bilbo_baggin]

That's the ring flah I have
bought it on eBay about 2 years back cost a bit more than that thought at the time.

Great bit of kit although it doesn't produce that much light.
If you pay postage paul I don't mind shipping it although buying one new would probably work out less

If the postage is £4.15 (Royal Mail), it might be worth a borrow, but you'd have to check if that would cover it. I'm skint having bought the damned lens, lol...

Paul.

[dpSparhawk]

They look very good Paul. Definitely looking forward to some of the summer bugs and what you'll get with it .


Steve Perry Sharpening? - Dont' stop.... belieeeeving, hold on to that feeeliiiinngg

[Bilbo_baggin]

They look very good Paul. Definitely looking forward to some of the summer bugs and what you'll get with it .

Aye - tried today for some water globbies but ISO had to go to 6400 to get any shutter speed so became unusable.

Steve Perry Sharpening? - Dont' stop.... belieeeeving, hold on to that feeeliiiinngg

Don't know him, but I'm lazy and any free action is a free action if it works and its free!!!


Paul.

[dpSparhawk]

Don't know him, but I'm lazy and any free action is a free action if it works and its free!!!


Paul.

hehe Steve Perry is/was the Singer from Journey (famous for that "Don't stop believing" song )

http://en.wikipedia.org/wiki/Steve_Perry

[Bilbo_baggin]

hehe Steve Perry is/was the Singer from Journey (famous for that "Don't stop believing" song )

http://en.wikipedia.org/wiki/Steve_Perry

Yeah - I knew that, but I don't know of the Photoshop chap Steve Perry, whos free action I downloaded

Paul.