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dbose
15-04-2010, 2:42pm
Hi Guys

I have been reading about close-up lenses vs. close-up filters and it appears that the former is a much better choice to retain quality. Is this true? I have a few questions on this topic:

- Does a close-up lens (say used on a 18-105 mm or 70-300mm) reduce the minimum focal distance?
- Also both my lenses are 67 mm - most close up lenses are only up to 58 which is unsuitable - I have heard about the Nikon 6T which is 62mm, is this good and available?
- How do I fit it to the 67mm lens?
- Is there any other alternatives?

Thanks a lot guys

DJ

ving
15-04-2010, 3:26pm
if you are going to use the filter type then i guess a step-down ring would have to be the go... my suggestion tho is to go for a macro lens of some sort rather than yet another piece of glass to shoot thru on the end of your lens.
:)

proper macro lenses are primes afaik, i have yet to see a zoom macro that was actually a macro and not just a closeup...

i am guessing you will want to know the difference between closeup and macro now right? macro is 1:1 (some say 1:2 is macro too) while closeup would be say 1:3 or above. there are alot of lenses that claim to be macro but only really do closeup.
what you get i guess depends on how close you want to get :)

dbose
15-04-2010, 3:44pm
Thanks mate - I do know the difference of a macro lens and close-up filters. I am currently looking into various macro lenses - in the interim I wanted to get something like the close-up lens to use with the other lenses. The macro I am looking at is either Nikon 105mm F2.8 or a cheaper Tamaron one.

I do not want to use a filter and would rather go for the close-up lens (I think the difference is that the close-up lens has double glasses or something like that). Hence my questions above.

OzzieTraveller
15-04-2010, 3:45pm
G'day DJ

Nice to hear from you & Welcome to the Forum

Firstly - there are no such animal as a "close up filter" ... a filter is an optical device that changes the colour or tone of an image - it has no effect upon focus. A lens, any lens is an optical device that is able to create an image and focus that image onto a receiving device, be it your eye or film or whatever

Close Up Lenses are optical devices similar to a spectacle lens. Mostly they are simple in construction, being one piece of glass (ie: one element), although in the US you can purchase 3-element close up lenses if you desire

Nearly all Close Up Lenses are designed to screw into the "attachment thread" on the front of a camera lens - and as we photographers use coloured & other filters, screwed into this "attachment thread" we loosely call it the "Filter Thread"

A Close Up Lens, being a lens, has a focal length, and the "strength" of the lens is referred to in "Dioptres". They are sold in sizes from about 30mm diameter to about 72mm diameter - check the Hoya catalogue if you like. The price is "about $1 per mm of diameter"

A "+1 Dioptre" lens has a focal length of 1-metre
A "+2 Dioptre" lens has a focal length of 1/2 metre
A "+3 Dioptre" lens has a focal length of 1/3 metre

For example ...
If you attach a +2 close up lens to a camera lens and that camera lens is set to infinity, then the close up lens will alter the camera's point of focus to 1/2 metre

If you screw the camera's focusing ring closer than infinity, then the new point of focus will become closer than 1/2 metre as well.

Being a simple, one-element optical device, it will never provide the empirical sharpness of a dedicated Macro-Lens for your SLR, however, these lenses are expensive as well.

Where the Close Up Lens becomes extremely useful is to lower the minimum focus point of a long focal length lens. Say you've got a 300 or 400mm lens which stops focus at 1.5metres. If you place a +2 close up lens onto that tele lens, then the lens immediately focuses at 1/2 metre ... great for insects or spiders who easily become frightened when a true Macro lens is used and it needs to come to 10-15cm from the subject to show it in detail

My camera lens is a 35mm to 420mm zoom - elsewhere on this forum (I think wildlife) you can see images of a Golden Orb Spider in its web, shot using a +2 close up lens from the 1/2 metre distance. If you look very critically at those images, you will see some colour changes towards the corners (looks a bit like a prism breaking up the colours) ~ this result you would not (should not) get with a true Macro lens, but there aren't too many 400mm macro lenses ...

Hope this has been of help to you - come back with more queries as they arise

Regards, Phil

dbose
15-04-2010, 4:29pm
Hi Phil

Thanks for the detailed response and it does make things clear. However, the question is when I search for close up lenses, it comes up with various (including Hoya) close up lenses with (+1d, +2d and +4d) at around 30 dollars and then it also comes up with the Canon 72mm Close-up Lens 500D (one lens) for about 160 dollars - why the price difference?

Also I am a fan of Bryan Peterson and was viewing one of his videos about close up photography (http://www.youtube.com/watch?v=U7rrEQxjHmA) and he mentions the usage of close up lenses (the Canon 500D) over close up filters (+1d, +2d etc.). What was he referring to?

Also my current lenses are both 67 mm. If I go for the Canon 72 mm 500D do I use a step up or step down adapter? Which is better?

Thanks again
DJ

Karl
15-04-2010, 10:30pm
Hi,

I am not sure if my reply will help you but I use a Sea & Sea 125mm Close Up lens for my underwater photography to assit in my underwater macro photos - it is a wet lens that screws onto my housing. The lens is like a big magnifying glass.

It has taken me a while to get use to this lens but now I am getting some awesome shots with it.

The main issue is the focus - it is a matter of milimeters between being in focus and out of focus. I am not sure what these lens are like for topside photography but for underwater they are very popular.

Karl

kwokask
15-04-2010, 10:37pm
If you are looking for a cheap way into macro, I would suggest extension tubes over close up lens. These can be used on any lens as they fit between the camera and the lens, and it also means there are no additional glass elements that could potentially reduce IQ.

OzzieTraveller
16-04-2010, 6:21pm
G'day DJ

This mob "http://www.d-d-photographics.com.au/filters.htm#closeup"
is advertising a +2 dioptre 67mm dia Close Up lens [but they are incorrectly calling it a filter] for a reasonable price. I suggest that you give it a go ~ it will go extremely well on your 70-300 lens

Regards, Phil

OzzieTraveller
16-04-2010, 6:37pm
G'day kwokask

Your suggestion for extension tubes is quite reasonable on the surface, except ... the use of ext'n tubes on a zoom lens is a complete disaster

The whole purpose of extending the nodal point of a lens away from the focal plane is to cause the point of focus to become closer than infinity and the lens maker does this via a helical ring (ie: the focus ring we twist). However, once an extension tube is inserted behind the main lens, as soon as the zoom ring is also activated, the nodal point is dramatically altered and the end result is that the point of focus alters to such a degree that the image is now unusable

From many years of experience, "yes" extension tubes can be of great use especially with some fixed-focal-length lenses, and the old rule is "when the exension in mm equals the focal length, you are at 1:1 image size" makes true macro photography a pleasure. BTW - my old 50mm film camera lens that I used for macro work went down to f90

For continuous (& serious) close-up work, then bellows on focusing rails are the best way to go. However, for "simple" close up work, especially with a long zoom lens ie: the 70-300 referred to above, a +2 dioptre close up lens for $50-60 is as good a way as any to get a quite acceptable result

Hope this helps a bit
Regards, Phil

simonr23
16-04-2010, 10:23pm
i bought a cheap set of close up lenses. a +4,+2 and +1 set. i have both the 4 and 2 on and it seems to work decently. i use it on my 70-300vr @ 70mm and it's fairly sharp still. very (too) shollow DOF at most aperatures, although at f16 it's still sharp and somewhat reasonable DOF.

i'm going to try my hand at image stacking to get better DOF.

dbose
18-04-2010, 9:45am
Hi All

Thanks for all your responses. I did some research regarding this topic. The main questions I had were:

1. What’s the difference between a Canon 500d close up (around AUD 170) lens vs. the ones that come in +1d, +2d and +4 d (like Hoya around AUD 50) - The main difference is that the Canon one is a double element one of which magnifies and the other (apparently) corrects image quality. The cheaper ones have a single element.
2. When extension tubes and when close up lenses - I agree with Phil’s response above. Ideally zoom lenses focus best at infinity and worst at the closest focal distance. By inserting an extension tube this gets worse and focus at minimum distance becomes harder. Also there is at least 1 to 2 stops of light that's cut out. When using a close up lens at the minimum focus distance this problem does not occur. So ideally it's better to use an extension tube for distance focusing and close up lens for close focusing.

Hope this makes sense. If the above is incorrect, please let me know and I will stand corrected.

OzzieTraveller
19-04-2010, 5:26pm
G'day DB

Two things - exten tubes firstly... Extension tubes are only (99%) used for close-up photos.
As you twist the focus ring on your lens - any lens - you will see that it moves away from the camera/sensor, and this is quite normal. But there is a limit to how far the lens will screw out, before falling to bits. By inserting an extn tube between the lens and the camera, you are creating that forward movement before twisting the lens focus ring to do further fine-tuning of the focus.

2- Secondly, close up lenses ... you get what you pay for. Yes the 2-element $150 Canon +2 lens should be a very good lens, and become very useful (if you go ahead and get one). I use a Hoya +2 and it does me okay. As you're talking about using it on your 70-300 zoom, tomorrow (on a new thread) I will post some sample images to show you the sort of thing you can do with a +2 on your zoom

Regards, Phil