[Bunch]

I'd much rather have a lens that produces sharp images at this price point than one with auto aperture at 50% more. The handling will be far easier also than any extension tube, coupled lens setup. This image is 3:1 with 56mm of extension tubes, an A series 100f4 macro, and an M series 50f4 macro reverse coupled on the end. Handheld it is a bare. Stopping down is the least of my problems. I look forward to purchasing the Venus.

[r0ckstarr]

I have the D FA 100 WR. It's the only macro lens I have ever owned, so it's all I have to compare with. Aperture control and AF excluded from my questions between the two. How would the Venus do when compared to the 100WR? The 100WR is 1:1, and the Venus is 1:2. Reproduction ratio vs. focal length is what I do not understand. Does the extra focal length of the 100WR make up for the difference between the two, or would cropping with 100WR to achieve the similar results? Or, does the Venus magnify more at 60mm than the 100WR does at 100mm? If you had/have the 100WR, would you still consider the Venus?

[filoxophy]

Well, if that's a "too personal" comment I don't know what to say without making it worse. It was a comment about your argument, just because it has the word "you" in it? Ok...

Keep calm and boriscleto.

[schneider]

Reproduction ratio vs. focal length is what I do not understand.

They are two different things. The reproduction ratio has nothing to do with focal length. With a shorter focal length you have to get closer to get ratio X as compared to a longer lens, but the ratio itself is a given. So if you want to get 1:2 with the DFA 100mm, you'll have to take a shot as close as you can and then crop it to 50% of the original size.

[BrianR]

How would the Venus do when compared to the 100WR? The 100WR is 1:1, and the Venus is 1:2. Reproduction ratio vs. focal length is what I do not understand. Does the extra focal length of the 100WR make up for the difference between the two, or would cropping with 100WR to achieve the similar results? Or, does the Venus magnify more at 60mm than the 100WR does at 100mm? If you had/have the 100WR, would you still consider the Venus?

The magnification ratio is (size of image projected on sensor) : (size of object in real life) or written as a single number (size of image projected on sensor)/(size of object in real life)

The Venus projects an image twice it's real life size, so it's 2:1 also written as 2.0x. The DFA100 can project a life sized image so it's 1:1 (also written 1.0x), and so are the other current pentax macros, da35/2.8 and the dfa50/2.8. Some of the older film-era macros can only project an object at half it's life size Super-Multi-Coated MACRO-TAKUMAR 100mm F4 and it's 1:2 (also written 0.5x).

With the DFA100mm (or other modern macro), you can fill the frame with an object the same size as the sensor, or roughly 16mm x 24mm. What changes between focal lengths is the minimum focusing distance you have to be at to get this magnification- the DFA100mm hits 1:1 at 30cm, the DFA50mm hits 1:1 at 19.5cm and the DA35mm hits 1:1 at 14cm (almost touching the front of the lens- these focusing distances are sensor to object). It can get complicated as the focal length of some lenses actually change as you turn the focusing ring and their guts move around (here's a neat animation of a nikon 85mm macro that drops down to 71mm at min. focus distance: Short Presentations, by Pierre Toscani).

With the Venus on a Pentax APS-C, you'd be able to 'fill the frame' with an object measuring 8mm by 12mm. With the older macro I linked to, the max is an object 32 mm x 48mm. The Venus wins for super small stuff, especially if you don't want to crop.

Whether it's worth it for DFA100mm owners or not is another question. For me, not so much. For the times I want to get more than the DFA100mm I can add a 1.4 teleconvertor or extension tubes (or both) or I can pull out reverse lens options which are probably in-between the DFA100mm and the Venus for convenience, but are cheap and can provide way more magnification than the Venus alone. For me, it doesn't add enough convenience over lens reversal or enough magnification over the DFA100 (+ TC) to be worth it, but ymmv.

[r0ckstarr]

They are two different things. The reproduction ratio has nothing to do with focal length. With a shorter focal length you have to get closer to get ratio X as compared to a longer lens, but the ratio itself is a given. So if you want to get 1:2 with the DFA 100mm, you'll have to take a shot as close as you can and then crop it to 50% of the original size.

The magnification ratio is

Thank you both for the informative replies. I now understand my confusion a lot better.

[Not a Number]

Here's a couple good articles on the subject:

Specifying the reproduction ratio

It's all about magnification

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Last edited by Not a Number; 02-28-2015 at 10:27 AM.

[Sliver-Surfer]

I totally forgot The most convenient way to shoot 2:1 with infinity on Pentax..Its hard to find but I have one. Pentax-A 4/100mm Dental
The close up 2:1 lens pops in and out with via magnet. I tried selling mine a year back with no takers. Glad I didn't

[pentaxus]

What I want to know is how close are you at 2:1. I prefer an unwieldy stack of extension tubes on a 100mm macro over something that is so close to the subject that it is impossible to light. If you like totally even light, ring led arrays or ring flashes can work but I prefer the texture you get with a separate flash. In tests I have covered part of a ring light with electrical tape to get more shape but . . . I still want to know how close.

[max_pyne]

i will do a similar comparison to that one: https://www.pentaxforums.com/forums/10-pentax-slr-lens-discussion/288412-look...estions-4.html as soon as the weather gets better...:-)

[Not a Number]

The first review linked below shows the working distance (front of lens barrel to subject) is about 6 cm or 2.4 inches. Not bad. The manual for the Pentax Auto Bellows A shows the working distance with the Pentax-A 50mm f/1.7 reversed at 2x to be 6.4 cm.

Venus 60mm f/2.8 macro 2:1 lens review | Nikon Rumors
Venus LAOWA 60mm f/2.8 2:1 Macro Lens User Review
Venus Lens 60mm F2.8 Macro Review - Lee Fletcher Photography
https://www.wimarys.com/venus-60mm-macro-lens-review/
Venus 60mm 2:1 macro lens | Up Close with Nature
Venus 60mm 2:1 Macro (for anyone who is interested) | Nikon Cafe
Lens Comparison – Venus 60mm f/2.8 2X Ultra-Macro VS Nikon AF-S 60mm f/2.8 G Macro | Venus Optics - Specialist in Macro Photography

A couple of flickr albums of shots using the lens
https://www.flickr.com/photos/orionmystery/sets/72157650638681152
https://www.flickr.com/photos/60601862@N00/sets/72157650545240737/

From Lee Fletcher's review:

Aperture Control

The lack of electronic aperture control is the stickler for me, and has been the biggest learning curve for me personally. Using any other Canon macro lens, I can look through the viewfinder and see my subject as brightly as if I had set the aperture at F2.8, but then when I press the shutter, the lens is stopped down to my desired F-stop at that point automatically and the picture taken. This makes initial focussing and composition a lot easier to pull off.

The Venus Lens will show you exactly what light is coming in through the lens, which at F11 or F16, isn’t a lot at all, so everything is very dark. I found when using my macro studio speedlites at large magnifications, I had to use a focus aid (my mobile phone LED “torch”) to help with this, and that worked just fine. For continuous lights, or in a bright environment, such as insect or flower photography outdoors, this is much less of an issue.

Is it a deal-breaker? Well, that I think depends on your patience, more than anything else, and how comfortable you are with your camera. Remember, this is how they used to do it on all cameras before the days of electronic SLRs. Being as honest as I can here, whilst it certainly takes more time and effort to really nail those high-magnification shots, due to the lack of available focussing light, it’s not a huge amount of extra work. For example, the flower shots in this review were all taken on a tripod, lens set at F2.8 to adjust focus, then once focus was achieved, the aperture ring turned to F11, and the camera triggered with a remote (with mirror lockup to minimise shake). Total extra time to compose and focus a shot? 10 seconds, if that.

If I was making my living off macro photography, and had to deal with large volumes of subjects in strict shooting deadlines, I’d maybe think twice about choosing a totally manual lens (for any sort of photography, really), but for general purpose macro, hobbyists, or more patient (or efficient) photographers than I, I think this lens is more than capable, and you will quickly learn to work around the focussing issues and incorporate those workarounds into your macro technique. If anything, it teaches you more, because you’re doing all the work, rather than relying on your camera’s usual helping hand.

I should say, that using the camera in Aperture priority mode, helps a lot, too. The camera still meters through the lens, so will automatically set your shutter speed to expose properly, even if it doesn’t control the aperture. In fact, in Aperture Priority mode, the only real difference from using any other lens, is that you’re setting your fixed aperture using a ring on the lens, rather than a dial on the camera. Of course, it is still a manual focus lens, but for me, I’m comfortable with that.

PS: It looks like they may be dumping the Venus name and inverted Infiniti logo: [Update: 2nd Feb] Venus Optics is now changing the brand logo into a fresh and energetic green logo. Our brand name will also transit from ‘VENUS’ to ‘LAOWA’. The lens shipped from now on will be printed with the name of ‘LAOWA’ instead.

Comparison of Pentax Dental 100mm vs Venus 60mm. The Venus has internal focusing so the length remains the same. I don't have the length of the 100mm at full extension.

[cheekygeek]

I totally forgot The most convenient way to shoot 2:1 with infinity on Pentax..Its hard to find but I have one. Pentax-A 4/100mm Dental
The close up 2:1 lens pops in and out with via magnet. I tried selling mine a year back with no takers. Glad I didn't

You are mistaken. 1:2 is not 2:1. The 2:1 is 4x the 1:2. The only Pentax macro that goes to 1:1 is the preset Macro-Takumar 50mm. The Venus lens is 2x that one.

[Hornet]

In case this hasn't been posted elsewhere in the thread or forum, here is a link to a Flickr group with some excellent examples of what can be done with this lens:
https://www.flickr.com/groups/2760818@N21/

[boriscleto]

You are mistaken. 1:2 is not 2:1. The 2:1 is 4x the 1:2. The only Pentax macro that goes to 1:1 is the preset Macro-Takumar 50mm. The Venus lens is 2x that one.

The last Pentax macros that were not 1:1 were the A 100/4 and the A 50/2.8. The A 100/2.8 and all later F/FA/DFA macros are 1:1. The DA 35/2.8 is 1:1 as well.

[Sliver-Surfer]

You are mistaken. 1:2 is not 2:1. The 2:1 is 4x the 1:2. The only Pentax macro that goes to 1:1 is the preset Macro-Takumar 50mm. The Venus lens is 2x that one.

I am not mistaken look at the yellow ratio markings on the barrel of the dental macro I provided. The dental macro is capable of 2:1 with the yellow close up lens.