Any experience with Hoffman modulation contrast? How it compares to more popular DIC techniques?
Is it available for objectives greater than 40x? (I can't find any)
Hoffman modulation contrast?
Re: Hoffman modulation contrast?
The reason why HMC is rare for more than 40x objective is that it is mainly used for petri dish (0.8-1.5mm cover) and inverted scope.
Its imaging quality, as I heard from an expert (Dave Jackson of Better Microscopy), is lower than good oblique or DIC.
It also has to use specialized objectives (with non removable HMC optical parts).
Overall, I think an amateur microphotographer would be better off staying with oblique for the same effect. Not to mention oblique is easy to DIY and much cheaper.
Its imaging quality, as I heard from an expert (Dave Jackson of Better Microscopy), is lower than good oblique or DIC.
It also has to use specialized objectives (with non removable HMC optical parts).
Overall, I think an amateur microphotographer would be better off staying with oblique for the same effect. Not to mention oblique is easy to DIY and much cheaper.
Re: Hoffman modulation contrast?
I purchased a used HM 40X objective and condenser many years ago and rather like the contrast enhancement that I can get. I have reflected DIC and it is by far superior, but for transmission, my only enhancement options are darkfield, phase, HM, Rheinberg, or something I found on the internet called P.A.C.O. A comparison of a gold nanoparticle agglomerate with both 40X phase and 40X HM are attached.
What I like is that there are no halos with HM which is an annoyance with phase. Also, since is basically a polarized filter off center from zero order light through the objective (and matching polar in the condenser) you can make infinite adjustments and use things like a red tint plate or the aforementioned P.A.C.O. device to get some very interesting enhacements.
HM does give a 3D aspect but it depends on the orientation of the sample to the filters and can be misleading of assumed height when it is not.
What I like is that there are no halos with HM which is an annoyance with phase. Also, since is basically a polarized filter off center from zero order light through the objective (and matching polar in the condenser) you can make infinite adjustments and use things like a red tint plate or the aforementioned P.A.C.O. device to get some very interesting enhacements.
HM does give a 3D aspect but it depends on the orientation of the sample to the filters and can be misleading of assumed height when it is not.
- Attachments
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- AuNP 400X HoffMod (McCrone)
- AuNP 400X HM.jpg (113.63 KiB) Viewed 3795 times
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- AuNP 400X phase (Zeiss)
- AuNP 400X Phase.jpg (116.6 KiB) Viewed 3795 times