Are close-up lenses really useful ...

[psychedelic_never]

Hi all,
I'm planning to do some Macro photography nothing exotic. I just wanted to know it the close up lenses are really useful? Also i have a 50 f/1.8 and Tamaron 75-300 1:2 macro lens, which will be better suited for Macro work alongwith the closeup lens, will i get a 1:1 magnification using them?
Sorry bout the number of questions...can't help it i'm really confused ???

I'm a novice hence won't be able to justify a purchase of MP-E 65 ... kidding
Thanks

[ron chappel]

Hi :)

Macro,like fisheye photography,tends not to need the very best image quality to work well because of the extreme nature of the subject.
So close up lenses definitely are a usefull option!
There are some types that are too cheap to consider though.Avoid the cheapest and probably also forget the genuine canon/nikon ones which are abit TOO good & expensive :shock:

Of your two lenses, the 70-300 would give greater magnification because it starts at 1:2 allready.
Would a close up lens take you to 1:1? Yes! You just have to select the right strength diopter (1,2,4,etc)
Working out magnification ratios is serious mathematical work which i promised myself i would never subject myself to :lol: :lol:

The easiest way is to try and see.I have some diopters here somewhere so i'll try to find them and try them on a lens set at 1:2 macro ratio.

[Scottes]

I'm in a rush... so I have to point you to the Search engine. Do a lookup on "tubes" and my name as the author. You'll get a few of my opinions on close-up lenses vs extension tubes, and what tubes can do.

Sorry... In a rush...

[Transfix]

I use a canon 100 USM f2.8. Great lens.

http://gallery.mikestrong.net

[Jesper]

Hi :)

Macro,like fisheye photography,tends not to need the very best image quality to work well because of the extreme nature of the subject.

Ron, what do you mean exactly by this? Why wouldn't you want the very best image quality?

I have the EF 100 f/2.8 Macro, which is a very nice and very sharp lens. Making 1:1 macro photos is NOT easy. To get a good photo you must use a tripod, because even the smallest vibration of your hands is visible at that magnification and the depth-of-field is so shallow (sometimes a fraction of a millimeter!) that it's very hard to get your subject in focus and keep it there.

[ron chappel]

Sorry,i've been real busy today.I will get a round to it sometime :oops:

For the moment i can explain what the diopter numbers do.
Close up lenses are technically called diopters.They come in different strengths,eg. #1,#2,#3,etc

A #1 will convert a lens so that it can't focus any further than 1 meter.
A # 2 will convert a lens so that it can't focus any further than 1/2 meter.
A # 3 will convert a lens so that it can't focus any further than 1/3 meter.
see the pattern?
(They can easily be stacked as well,ie. a #1,#2 and #3 would equal a #6 diopter)
They also of course give a corresponding decrease in minimum focus distance ,but as all lenses have different minimum focus distances it is very tricky working out what magnification you will end up with.

When you buy diopters,the manufacturer will usually give charts to show how much they work with certain model lenses.
And as i said above,it's easier just trying most times

I'll be back later with some results hopefully

[psychedelic_never]

Guys thanks a ton for the response and i guess closeup lens is the way to go as i'm a bit stripped of cash and loan :( . As for now i'm off to look for some close up lenses.

[ron chappel]

OK

I found a #1 close up lens and tried it on several lenses.

I'll assume you have a digital camera (300D,10 etc) -otherwise tell me because these numbers won't meant anything :shock:

Your tamron lens at 1:2 will currently fill the frame with an object 45x30mm.
With a #1 diopter this will decrease to about 33x22mm.
Not quite 1:1 on a digital but slightly better than the traditional 1:1 on film cameras (which was 36x24mm)

I'm guessing that you would need about 3(?) diopters to get to the true digital 1:1 of 22.5x15mm



The 50/1.8 at closest focus covers 140x90mm.With the #1 lens this only comes down to 90x60mm,so it's going to need a serious number/strength of close up lenses to get usefull magnification :shock:

[psychedelic_never]

hi ron,
thanks a lot for the math and i think i'm about to buy the diopter set of 3 with +1, +2 and +4 power.
thanks again
yes and i have a 300D

[ron chappel]

Yes they usually sell them in a set like that.

Just avoid the cheapest and you'll do ok :)